Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

22 files changed, 6723 insertions, 0 deletions

diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
new file mode 100644
index 000000000..5ead3c3de
--- /dev/null
+++ b/arch/arm64/mm/Makefile
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y				:= dma-mapping.o extable.o fault.o init.o \
+				   cache.o copypage.o flush.o \
+				   ioremap.o mmap.o pgd.o mmu.o \
+				   context.o proc.o pageattr.o
+obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o
+obj-$(CONFIG_PTDUMP_CORE)	+= ptdump.o
+obj-$(CONFIG_PTDUMP_DEBUGFS)	+= ptdump_debugfs.o
+obj-$(CONFIG_NUMA)		+= numa.o
+obj-$(CONFIG_DEBUG_VIRTUAL)	+= physaddr.o
+obj-$(CONFIG_ARM64_MTE)		+= mteswap.o
+KASAN_SANITIZE_physaddr.o	+= n
+
+obj-$(CONFIG_KASAN)		+= kasan_init.o
+KASAN_SANITIZE_kasan_init.o	:= n
diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S
new file mode 100644
index 000000000..7b8158ae3
--- /dev/null
+++ b/arch/arm64/mm/cache.S
@@ -0,0 +1,244 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Cache maintenance
+ *
+ * Copyright (C) 2001 Deep Blue Solutions Ltd.
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative.h>
+#include <asm/asm-uaccess.h>
+
+/*
+ *	flush_icache_range(start,end)
+ *
+ *	Ensure that the I and D caches are coherent within specified region.
+ *	This is typically used when code has been written to a memory region,
+ *	and will be executed.
+ *
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+SYM_FUNC_START(__flush_icache_range)
+	/* FALLTHROUGH */
+
+/*
+ *	__flush_cache_user_range(start,end)
+ *
+ *	Ensure that the I and D caches are coherent within specified region.
+ *	This is typically used when code has been written to a memory region,
+ *	and will be executed.
+ *
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+SYM_FUNC_START(__flush_cache_user_range)
+	uaccess_ttbr0_enable x2, x3, x4
+alternative_if ARM64_HAS_CACHE_IDC
+	dsb	ishst
+	b	7f
+alternative_else_nop_endif
+	dcache_line_size x2, x3
+	sub	x3, x2, #1
+	bic	x4, x0, x3
+1:
+user_alt 9f, "dc cvau, x4",  "dc civac, x4",  ARM64_WORKAROUND_CLEAN_CACHE
+	add	x4, x4, x2
+	cmp	x4, x1
+	b.lo	1b
+	dsb	ish
+
+7:
+alternative_if ARM64_HAS_CACHE_DIC
+	isb
+	b	8f
+alternative_else_nop_endif
+	invalidate_icache_by_line x0, x1, x2, x3, 9f
+8:	mov	x0, #0
+1:
+	uaccess_ttbr0_disable x1, x2
+	ret
+9:
+	mov	x0, #-EFAULT
+	b	1b
+SYM_FUNC_END(__flush_icache_range)
+SYM_FUNC_END(__flush_cache_user_range)
+
+/*
+ *	invalidate_icache_range(start,end)
+ *
+ *	Ensure that the I cache is invalid within specified region.
+ *
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+SYM_FUNC_START(invalidate_icache_range)
+alternative_if ARM64_HAS_CACHE_DIC
+	mov	x0, xzr
+	isb
+	ret
+alternative_else_nop_endif
+
+	uaccess_ttbr0_enable x2, x3, x4
+
+	invalidate_icache_by_line x0, x1, x2, x3, 2f
+	mov	x0, xzr
+1:
+	uaccess_ttbr0_disable x1, x2
+	ret
+2:
+	mov	x0, #-EFAULT
+	b	1b
+SYM_FUNC_END(invalidate_icache_range)
+
+/*
+ *	__flush_dcache_area(kaddr, size)
+ *
+ *	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ *	are cleaned and invalidated to the PoC.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+SYM_FUNC_START_PI(__flush_dcache_area)
+	dcache_by_line_op civac, sy, x0, x1, x2, x3
+	ret
+SYM_FUNC_END_PI(__flush_dcache_area)
+
+/*
+ *	__clean_dcache_area_pou(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are cleaned to the PoU.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+SYM_FUNC_START(__clean_dcache_area_pou)
+alternative_if ARM64_HAS_CACHE_IDC
+	dsb	ishst
+	ret
+alternative_else_nop_endif
+	dcache_by_line_op cvau, ish, x0, x1, x2, x3
+	ret
+SYM_FUNC_END(__clean_dcache_area_pou)
+
+/*
+ *	__inval_dcache_area(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are invalidated. Any partial lines at the ends of the interval are
+ *	also cleaned to PoC to prevent data loss.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+SYM_FUNC_START_LOCAL(__dma_inv_area)
+SYM_FUNC_START_PI(__inval_dcache_area)
+	/* FALLTHROUGH */
+
+/*
+ *	__dma_inv_area(start, size)
+ *	- start   - virtual start address of region
+ *	- size    - size in question
+ */
+	add	x1, x1, x0
+	dcache_line_size x2, x3
+	sub	x3, x2, #1
+	tst	x1, x3				// end cache line aligned?
+	bic	x1, x1, x3
+	b.eq	1f
+	dc	civac, x1			// clean & invalidate D / U line
+1:	tst	x0, x3				// start cache line aligned?
+	bic	x0, x0, x3
+	b.eq	2f
+	dc	civac, x0			// clean & invalidate D / U line
+	b	3f
+2:	dc	ivac, x0			// invalidate D / U line
+3:	add	x0, x0, x2
+	cmp	x0, x1
+	b.lo	2b
+	dsb	sy
+	ret
+SYM_FUNC_END_PI(__inval_dcache_area)
+SYM_FUNC_END(__dma_inv_area)
+
+/*
+ *	__clean_dcache_area_poc(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are cleaned to the PoC.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+SYM_FUNC_START_LOCAL(__dma_clean_area)
+SYM_FUNC_START_PI(__clean_dcache_area_poc)
+	/* FALLTHROUGH */
+
+/*
+ *	__dma_clean_area(start, size)
+ *	- start   - virtual start address of region
+ *	- size    - size in question
+ */
+	dcache_by_line_op cvac, sy, x0, x1, x2, x3
+	ret
+SYM_FUNC_END_PI(__clean_dcache_area_poc)
+SYM_FUNC_END(__dma_clean_area)
+
+/*
+ *	__clean_dcache_area_pop(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are cleaned to the PoP.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+SYM_FUNC_START_PI(__clean_dcache_area_pop)
+	alternative_if_not ARM64_HAS_DCPOP
+	b	__clean_dcache_area_poc
+	alternative_else_nop_endif
+	dcache_by_line_op cvap, sy, x0, x1, x2, x3
+	ret
+SYM_FUNC_END_PI(__clean_dcache_area_pop)
+
+/*
+ *	__dma_flush_area(start, size)
+ *
+ *	clean & invalidate D / U line
+ *
+ *	- start   - virtual start address of region
+ *	- size    - size in question
+ */
+SYM_FUNC_START_PI(__dma_flush_area)
+	dcache_by_line_op civac, sy, x0, x1, x2, x3
+	ret
+SYM_FUNC_END_PI(__dma_flush_area)
+
+/*
+ *	__dma_map_area(start, size, dir)
+ *	- start	- kernel virtual start address
+ *	- size	- size of region
+ *	- dir	- DMA direction
+ */
+SYM_FUNC_START_PI(__dma_map_area)
+	b	__dma_clean_area
+SYM_FUNC_END_PI(__dma_map_area)
+
+/*
+ *	__dma_unmap_area(start, size, dir)
+ *	- start	- kernel virtual start address
+ *	- size	- size of region
+ *	- dir	- DMA direction
+ */
+SYM_FUNC_START_PI(__dma_unmap_area)
+	cmp	w2, #DMA_TO_DEVICE
+	b.ne	__dma_inv_area
+	ret
+SYM_FUNC_END_PI(__dma_unmap_area)
diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
new file mode 100644
index 000000000..001737a8f
--- /dev/null
+++ b/arch/arm64/mm/context.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/context.c
+ *
+ * Copyright (C) 2002-2003 Deep Blue Solutions Ltd, all rights reserved.
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+
+#include <asm/cpufeature.h>
+#include <asm/mmu_context.h>
+#include <asm/smp.h>
+#include <asm/tlbflush.h>
+
+static u32 asid_bits;
+static DEFINE_RAW_SPINLOCK(cpu_asid_lock);
+
+static atomic64_t asid_generation;
+static unsigned long *asid_map;
+
+static DEFINE_PER_CPU(atomic64_t, active_asids);
+static DEFINE_PER_CPU(u64, reserved_asids);
+static cpumask_t tlb_flush_pending;
+
+static unsigned long max_pinned_asids;
+static unsigned long nr_pinned_asids;
+static unsigned long *pinned_asid_map;
+
+#define ASID_MASK		(~GENMASK(asid_bits - 1, 0))
+#define ASID_FIRST_VERSION	(1UL << asid_bits)
+
+#define NUM_USER_ASIDS		ASID_FIRST_VERSION
+#define asid2idx(asid)		((asid) & ~ASID_MASK)
+#define idx2asid(idx)		asid2idx(idx)
+
+/* Get the ASIDBits supported by the current CPU */
+static u32 get_cpu_asid_bits(void)
+{
+	u32 asid;
+	int fld = cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64MMFR0_EL1),
+						ID_AA64MMFR0_ASID_SHIFT);
+
+	switch (fld) {
+	default:
+		pr_warn("CPU%d: Unknown ASID size (%d); assuming 8-bit\n",
+					smp_processor_id(),  fld);
+		fallthrough;
+	case 0:
+		asid = 8;
+		break;
+	case 2:
+		asid = 16;
+	}
+
+	return asid;
+}
+
+/* Check if the current cpu's ASIDBits is compatible with asid_bits */
+void verify_cpu_asid_bits(void)
+{
+	u32 asid = get_cpu_asid_bits();
+
+	if (asid < asid_bits) {
+		/*
+		 * We cannot decrease the ASID size at runtime, so panic if we support
+		 * fewer ASID bits than the boot CPU.
+		 */
+		pr_crit("CPU%d: smaller ASID size(%u) than boot CPU (%u)\n",
+				smp_processor_id(), asid, asid_bits);
+		cpu_panic_kernel();
+	}
+}
+
+static void set_kpti_asid_bits(unsigned long *map)
+{
+	unsigned int len = BITS_TO_LONGS(NUM_USER_ASIDS) * sizeof(unsigned long);
+	/*
+	 * In case of KPTI kernel/user ASIDs are allocated in
+	 * pairs, the bottom bit distinguishes the two: if it
+	 * is set, then the ASID will map only userspace. Thus
+	 * mark even as reserved for kernel.
+	 */
+	memset(map, 0xaa, len);
+}
+
+static void set_reserved_asid_bits(void)
+{
+	if (pinned_asid_map)
+		bitmap_copy(asid_map, pinned_asid_map, NUM_USER_ASIDS);
+	else if (arm64_kernel_unmapped_at_el0())
+		set_kpti_asid_bits(asid_map);
+	else
+		bitmap_clear(asid_map, 0, NUM_USER_ASIDS);
+}
+
+#define asid_gen_match(asid) \
+	(!(((asid) ^ atomic64_read(&asid_generation)) >> asid_bits))
+
+static void flush_context(void)
+{
+	int i;
+	u64 asid;
+
+	/* Update the list of reserved ASIDs and the ASID bitmap. */
+	set_reserved_asid_bits();
+
+	for_each_possible_cpu(i) {
+		asid = atomic64_xchg_relaxed(&per_cpu(active_asids, i), 0);
+		/*
+		 * If this CPU has already been through a
+		 * rollover, but hasn't run another task in
+		 * the meantime, we must preserve its reserved
+		 * ASID, as this is the only trace we have of
+		 * the process it is still running.
+		 */
+		if (asid == 0)
+			asid = per_cpu(reserved_asids, i);
+		__set_bit(asid2idx(asid), asid_map);
+		per_cpu(reserved_asids, i) = asid;
+	}
+
+	/*
+	 * Queue a TLB invalidation for each CPU to perform on next
+	 * context-switch
+	 */
+	cpumask_setall(&tlb_flush_pending);
+}
+
+static bool check_update_reserved_asid(u64 asid, u64 newasid)
+{
+	int cpu;
+	bool hit = false;
+
+	/*
+	 * Iterate over the set of reserved ASIDs looking for a match.
+	 * If we find one, then we can update our mm to use newasid
+	 * (i.e. the same ASID in the current generation) but we can't
+	 * exit the loop early, since we need to ensure that all copies
+	 * of the old ASID are updated to reflect the mm. Failure to do
+	 * so could result in us missing the reserved ASID in a future
+	 * generation.
+	 */
+	for_each_possible_cpu(cpu) {
+		if (per_cpu(reserved_asids, cpu) == asid) {
+			hit = true;
+			per_cpu(reserved_asids, cpu) = newasid;
+		}
+	}
+
+	return hit;
+}
+
+static u64 new_context(struct mm_struct *mm)
+{
+	static u32 cur_idx = 1;
+	u64 asid = atomic64_read(&mm->context.id);
+	u64 generation = atomic64_read(&asid_generation);
+
+	if (asid != 0) {
+		u64 newasid = generation | (asid & ~ASID_MASK);
+
+		/*
+		 * If our current ASID was active during a rollover, we
+		 * can continue to use it and this was just a false alarm.
+		 */
+		if (check_update_reserved_asid(asid, newasid))
+			return newasid;
+
+		/*
+		 * If it is pinned, we can keep using it. Note that reserved
+		 * takes priority, because even if it is also pinned, we need to
+		 * update the generation into the reserved_asids.
+		 */
+		if (refcount_read(&mm->context.pinned))
+			return newasid;
+
+		/*
+		 * We had a valid ASID in a previous life, so try to re-use
+		 * it if possible.
+		 */
+		if (!__test_and_set_bit(asid2idx(asid), asid_map))
+			return newasid;
+	}
+
+	/*
+	 * Allocate a free ASID. If we can't find one, take a note of the
+	 * currently active ASIDs and mark the TLBs as requiring flushes.  We
+	 * always count from ASID #2 (index 1), as we use ASID #0 when setting
+	 * a reserved TTBR0 for the init_mm and we allocate ASIDs in even/odd
+	 * pairs.
+	 */
+	asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, cur_idx);
+	if (asid != NUM_USER_ASIDS)
+		goto set_asid;
+
+	/* We're out of ASIDs, so increment the global generation count */
+	generation = atomic64_add_return_relaxed(ASID_FIRST_VERSION,
+						 &asid_generation);
+	flush_context();
+
+	/* We have more ASIDs than CPUs, so this will always succeed */
+	asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, 1);
+
+set_asid:
+	__set_bit(asid, asid_map);
+	cur_idx = asid;
+	return idx2asid(asid) | generation;
+}
+
+void check_and_switch_context(struct mm_struct *mm)
+{
+	unsigned long flags;
+	unsigned int cpu;
+	u64 asid, old_active_asid;
+
+	if (system_supports_cnp())
+		cpu_set_reserved_ttbr0();
+
+	asid = atomic64_read(&mm->context.id);
+
+	/*
+	 * The memory ordering here is subtle.
+	 * If our active_asids is non-zero and the ASID matches the current
+	 * generation, then we update the active_asids entry with a relaxed
+	 * cmpxchg. Racing with a concurrent rollover means that either:
+	 *
+	 * - We get a zero back from the cmpxchg and end up waiting on the
+	 *   lock. Taking the lock synchronises with the rollover and so
+	 *   we are forced to see the updated generation.
+	 *
+	 * - We get a valid ASID back from the cmpxchg, which means the
+	 *   relaxed xchg in flush_context will treat us as reserved
+	 *   because atomic RmWs are totally ordered for a given location.
+	 */
+	old_active_asid = atomic64_read(this_cpu_ptr(&active_asids));
+	if (old_active_asid && asid_gen_match(asid) &&
+	    atomic64_cmpxchg_relaxed(this_cpu_ptr(&active_asids),
+				     old_active_asid, asid))
+		goto switch_mm_fastpath;
+
+	raw_spin_lock_irqsave(&cpu_asid_lock, flags);
+	/* Check that our ASID belongs to the current generation. */
+	asid = atomic64_read(&mm->context.id);
+	if (!asid_gen_match(asid)) {
+		asid = new_context(mm);
+		atomic64_set(&mm->context.id, asid);
+	}
+
+	cpu = smp_processor_id();
+	if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending))
+		local_flush_tlb_all();
+
+	atomic64_set(this_cpu_ptr(&active_asids), asid);
+	raw_spin_unlock_irqrestore(&cpu_asid_lock, flags);
+
+switch_mm_fastpath:
+
+	arm64_apply_bp_hardening();
+
+	/*
+	 * Defer TTBR0_EL1 setting for user threads to uaccess_enable() when
+	 * emulating PAN.
+	 */
+	if (!system_uses_ttbr0_pan())
+		cpu_switch_mm(mm->pgd, mm);
+}
+
+unsigned long arm64_mm_context_get(struct mm_struct *mm)
+{
+	unsigned long flags;
+	u64 asid;
+
+	if (!pinned_asid_map)
+		return 0;
+
+	raw_spin_lock_irqsave(&cpu_asid_lock, flags);
+
+	asid = atomic64_read(&mm->context.id);
+
+	if (refcount_inc_not_zero(&mm->context.pinned))
+		goto out_unlock;
+
+	if (nr_pinned_asids >= max_pinned_asids) {
+		asid = 0;
+		goto out_unlock;
+	}
+
+	if (!asid_gen_match(asid)) {
+		/*
+		 * We went through one or more rollover since that ASID was
+		 * used. Ensure that it is still valid, or generate a new one.
+		 */
+		asid = new_context(mm);
+		atomic64_set(&mm->context.id, asid);
+	}
+
+	nr_pinned_asids++;
+	__set_bit(asid2idx(asid), pinned_asid_map);
+	refcount_set(&mm->context.pinned, 1);
+
+out_unlock:
+	raw_spin_unlock_irqrestore(&cpu_asid_lock, flags);
+
+	asid &= ~ASID_MASK;
+
+	/* Set the equivalent of USER_ASID_BIT */
+	if (asid && arm64_kernel_unmapped_at_el0())
+		asid |= 1;
+
+	return asid;
+}
+EXPORT_SYMBOL_GPL(arm64_mm_context_get);
+
+void arm64_mm_context_put(struct mm_struct *mm)
+{
+	unsigned long flags;
+	u64 asid = atomic64_read(&mm->context.id);
+
+	if (!pinned_asid_map)
+		return;
+
+	raw_spin_lock_irqsave(&cpu_asid_lock, flags);
+
+	if (refcount_dec_and_test(&mm->context.pinned)) {
+		__clear_bit(asid2idx(asid), pinned_asid_map);
+		nr_pinned_asids--;
+	}
+
+	raw_spin_unlock_irqrestore(&cpu_asid_lock, flags);
+}
+EXPORT_SYMBOL_GPL(arm64_mm_context_put);
+
+/* Errata workaround post TTBRx_EL1 update. */
+asmlinkage void post_ttbr_update_workaround(void)
+{
+	if (!IS_ENABLED(CONFIG_CAVIUM_ERRATUM_27456))
+		return;
+
+	asm(ALTERNATIVE("nop; nop; nop",
+			"ic iallu; dsb nsh; isb",
+			ARM64_WORKAROUND_CAVIUM_27456));
+}
+
+void cpu_do_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm)
+{
+	unsigned long ttbr1 = read_sysreg(ttbr1_el1);
+	unsigned long asid = ASID(mm);
+	unsigned long ttbr0 = phys_to_ttbr(pgd_phys);
+
+	/* Skip CNP for the reserved ASID */
+	if (system_supports_cnp() && asid)
+		ttbr0 |= TTBR_CNP_BIT;
+
+	/* SW PAN needs a copy of the ASID in TTBR0 for entry */
+	if (IS_ENABLED(CONFIG_ARM64_SW_TTBR0_PAN))
+		ttbr0 |= FIELD_PREP(TTBR_ASID_MASK, asid);
+
+	/* Set ASID in TTBR1 since TCR.A1 is set */
+	ttbr1 &= ~TTBR_ASID_MASK;
+	ttbr1 |= FIELD_PREP(TTBR_ASID_MASK, asid);
+
+	write_sysreg(ttbr1, ttbr1_el1);
+	isb();
+	write_sysreg(ttbr0, ttbr0_el1);
+	isb();
+	post_ttbr_update_workaround();
+}
+
+static int asids_update_limit(void)
+{
+	unsigned long num_available_asids = NUM_USER_ASIDS;
+
+	if (arm64_kernel_unmapped_at_el0()) {
+		num_available_asids /= 2;
+		if (pinned_asid_map)
+			set_kpti_asid_bits(pinned_asid_map);
+	}
+	/*
+	 * Expect allocation after rollover to fail if we don't have at least
+	 * one more ASID than CPUs. ASID #0 is reserved for init_mm.
+	 */
+	WARN_ON(num_available_asids - 1 <= num_possible_cpus());
+	pr_info("ASID allocator initialised with %lu entries\n",
+		num_available_asids);
+
+	/*
+	 * There must always be an ASID available after rollover. Ensure that,
+	 * even if all CPUs have a reserved ASID and the maximum number of ASIDs
+	 * are pinned, there still is at least one empty slot in the ASID map.
+	 */
+	max_pinned_asids = num_available_asids - num_possible_cpus() - 2;
+	return 0;
+}
+arch_initcall(asids_update_limit);
+
+static int asids_init(void)
+{
+	asid_bits = get_cpu_asid_bits();
+	atomic64_set(&asid_generation, ASID_FIRST_VERSION);
+	asid_map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS), sizeof(*asid_map),
+			   GFP_KERNEL);
+	if (!asid_map)
+		panic("Failed to allocate bitmap for %lu ASIDs\n",
+		      NUM_USER_ASIDS);
+
+	pinned_asid_map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS),
+				  sizeof(*pinned_asid_map), GFP_KERNEL);
+	nr_pinned_asids = 0;
+
+	/*
+	 * We cannot call set_reserved_asid_bits() here because CPU
+	 * caps are not finalized yet, so it is safer to assume KPTI
+	 * and reserve kernel ASID's from beginning.
+	 */
+	if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0))
+		set_kpti_asid_bits(asid_map);
+	return 0;
+}
+early_initcall(asids_init);
diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
new file mode 100644
index 000000000..24913271e
--- /dev/null
+++ b/arch/arm64/mm/copypage.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/copypage.c
+ *
+ * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved.
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/bitops.h>
+#include <linux/mm.h>
+
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/cpufeature.h>
+#include <asm/mte.h>
+
+void copy_highpage(struct page *to, struct page *from)
+{
+	void *kto = page_address(to);
+	void *kfrom = page_address(from);
+
+	copy_page(kto, kfrom);
+
+	if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) {
+		set_bit(PG_mte_tagged, &to->flags);
+		mte_copy_page_tags(kto, kfrom);
+	}
+}
+EXPORT_SYMBOL(copy_highpage);
+
+void copy_user_highpage(struct page *to, struct page *from,
+			unsigned long vaddr, struct vm_area_struct *vma)
+{
+	copy_highpage(to, from);
+	flush_dcache_page(to);
+}
+EXPORT_SYMBOL_GPL(copy_user_highpage);
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
new file mode 100644
index 000000000..93e87b287
--- /dev/null
+++ b/arch/arm64/mm/dma-mapping.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#include <linux/gfp.h>
+#include <linux/cache.h>
+#include <linux/dma-map-ops.h>
+#include <linux/dma-iommu.h>
+#include <xen/xen.h>
+#include <xen/swiotlb-xen.h>
+
+#include <asm/cacheflush.h>
+
+void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	__dma_map_area(phys_to_virt(paddr), size, dir);
+}
+
+void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	__dma_unmap_area(phys_to_virt(paddr), size, dir);
+}
+
+void arch_dma_prep_coherent(struct page *page, size_t size)
+{
+	__dma_flush_area(page_address(page), size);
+}
+
+#ifdef CONFIG_IOMMU_DMA
+void arch_teardown_dma_ops(struct device *dev)
+{
+	dev->dma_ops = NULL;
+}
+#endif
+
+void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
+			const struct iommu_ops *iommu, bool coherent)
+{
+	int cls = cache_line_size_of_cpu();
+
+	WARN_TAINT(!coherent && cls > ARCH_DMA_MINALIGN,
+		   TAINT_CPU_OUT_OF_SPEC,
+		   "%s %s: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (%d < %d)",
+		   dev_driver_string(dev), dev_name(dev),
+		   ARCH_DMA_MINALIGN, cls);
+
+	dev->dma_coherent = coherent;
+	if (iommu)
+		iommu_setup_dma_ops(dev, dma_base, size);
+
+#ifdef CONFIG_XEN
+	if (xen_initial_domain())
+		dev->dma_ops = &xen_swiotlb_dma_ops;
+#endif
+}
diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c
new file mode 100644
index 000000000..aa0060178
--- /dev/null
+++ b/arch/arm64/mm/extable.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Based on arch/arm/mm/extable.c
+ */
+
+#include <linux/extable.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *fixup;
+
+	fixup = search_exception_tables(instruction_pointer(regs));
+	if (!fixup)
+		return 0;
+
+	if (in_bpf_jit(regs))
+		return arm64_bpf_fixup_exception(fixup, regs);
+
+	regs->pc = (unsigned long)&fixup->fixup + fixup->fixup;
+	return 1;
+}
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
new file mode 100644
index 000000000..d8baedd16
--- /dev/null
+++ b/arch/arm64/mm/fault.c
@@ -0,0 +1,855 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/fault.c
+ *
+ * Copyright (C) 1995  Linus Torvalds
+ * Copyright (C) 1995-2004 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitfield.h>
+#include <linux/extable.h>
+#include <linux/signal.h>
+#include <linux/mm.h>
+#include <linux/hardirq.h>
+#include <linux/init.h>
+#include <linux/kprobes.h>
+#include <linux/uaccess.h>
+#include <linux/page-flags.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/debug.h>
+#include <linux/highmem.h>
+#include <linux/perf_event.h>
+#include <linux/preempt.h>
+#include <linux/hugetlb.h>
+
+#include <asm/acpi.h>
+#include <asm/bug.h>
+#include <asm/cmpxchg.h>
+#include <asm/cpufeature.h>
+#include <asm/exception.h>
+#include <asm/daifflags.h>
+#include <asm/debug-monitors.h>
+#include <asm/esr.h>
+#include <asm/kprobes.h>
+#include <asm/processor.h>
+#include <asm/sysreg.h>
+#include <asm/system_misc.h>
+#include <asm/tlbflush.h>
+#include <asm/traps.h>
+
+struct fault_info {
+	int	(*fn)(unsigned long addr, unsigned int esr,
+		      struct pt_regs *regs);
+	int	sig;
+	int	code;
+	const char *name;
+};
+
+static const struct fault_info fault_info[];
+static struct fault_info debug_fault_info[];
+
+static inline const struct fault_info *esr_to_fault_info(unsigned int esr)
+{
+	return fault_info + (esr & ESR_ELx_FSC);
+}
+
+static inline const struct fault_info *esr_to_debug_fault_info(unsigned int esr)
+{
+	return debug_fault_info + DBG_ESR_EVT(esr);
+}
+
+static void data_abort_decode(unsigned int esr)
+{
+	pr_alert("Data abort info:\n");
+
+	if (esr & ESR_ELx_ISV) {
+		pr_alert("  Access size = %u byte(s)\n",
+			 1U << ((esr & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT));
+		pr_alert("  SSE = %lu, SRT = %lu\n",
+			 (esr & ESR_ELx_SSE) >> ESR_ELx_SSE_SHIFT,
+			 (esr & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT);
+		pr_alert("  SF = %lu, AR = %lu\n",
+			 (esr & ESR_ELx_SF) >> ESR_ELx_SF_SHIFT,
+			 (esr & ESR_ELx_AR) >> ESR_ELx_AR_SHIFT);
+	} else {
+		pr_alert("  ISV = 0, ISS = 0x%08lx\n", esr & ESR_ELx_ISS_MASK);
+	}
+
+	pr_alert("  CM = %lu, WnR = %lu\n",
+		 (esr & ESR_ELx_CM) >> ESR_ELx_CM_SHIFT,
+		 (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT);
+}
+
+static void mem_abort_decode(unsigned int esr)
+{
+	pr_alert("Mem abort info:\n");
+
+	pr_alert("  ESR = 0x%08x\n", esr);
+	pr_alert("  EC = 0x%02lx: %s, IL = %u bits\n",
+		 ESR_ELx_EC(esr), esr_get_class_string(esr),
+		 (esr & ESR_ELx_IL) ? 32 : 16);
+	pr_alert("  SET = %lu, FnV = %lu\n",
+		 (esr & ESR_ELx_SET_MASK) >> ESR_ELx_SET_SHIFT,
+		 (esr & ESR_ELx_FnV) >> ESR_ELx_FnV_SHIFT);
+	pr_alert("  EA = %lu, S1PTW = %lu\n",
+		 (esr & ESR_ELx_EA) >> ESR_ELx_EA_SHIFT,
+		 (esr & ESR_ELx_S1PTW) >> ESR_ELx_S1PTW_SHIFT);
+
+	if (esr_is_data_abort(esr))
+		data_abort_decode(esr);
+}
+
+static inline unsigned long mm_to_pgd_phys(struct mm_struct *mm)
+{
+	/* Either init_pg_dir or swapper_pg_dir */
+	if (mm == &init_mm)
+		return __pa_symbol(mm->pgd);
+
+	return (unsigned long)virt_to_phys(mm->pgd);
+}
+
+/*
+ * Dump out the page tables associated with 'addr' in the currently active mm.
+ */
+static void show_pte(unsigned long addr)
+{
+	struct mm_struct *mm;
+	pgd_t *pgdp;
+	pgd_t pgd;
+
+	if (is_ttbr0_addr(addr)) {
+		/* TTBR0 */
+		mm = current->active_mm;
+		if (mm == &init_mm) {
+			pr_alert("[%016lx] user address but active_mm is swapper\n",
+				 addr);
+			return;
+		}
+	} else if (is_ttbr1_addr(addr)) {
+		/* TTBR1 */
+		mm = &init_mm;
+	} else {
+		pr_alert("[%016lx] address between user and kernel address ranges\n",
+			 addr);
+		return;
+	}
+
+	pr_alert("%s pgtable: %luk pages, %llu-bit VAs, pgdp=%016lx\n",
+		 mm == &init_mm ? "swapper" : "user", PAGE_SIZE / SZ_1K,
+		 vabits_actual, mm_to_pgd_phys(mm));
+	pgdp = pgd_offset(mm, addr);
+	pgd = READ_ONCE(*pgdp);
+	pr_alert("[%016lx] pgd=%016llx", addr, pgd_val(pgd));
+
+	do {
+		p4d_t *p4dp, p4d;
+		pud_t *pudp, pud;
+		pmd_t *pmdp, pmd;
+		pte_t *ptep, pte;
+
+		if (pgd_none(pgd) || pgd_bad(pgd))
+			break;
+
+		p4dp = p4d_offset(pgdp, addr);
+		p4d = READ_ONCE(*p4dp);
+		pr_cont(", p4d=%016llx", p4d_val(p4d));
+		if (p4d_none(p4d) || p4d_bad(p4d))
+			break;
+
+		pudp = pud_offset(p4dp, addr);
+		pud = READ_ONCE(*pudp);
+		pr_cont(", pud=%016llx", pud_val(pud));
+		if (pud_none(pud) || pud_bad(pud))
+			break;
+
+		pmdp = pmd_offset(pudp, addr);
+		pmd = READ_ONCE(*pmdp);
+		pr_cont(", pmd=%016llx", pmd_val(pmd));
+		if (pmd_none(pmd) || pmd_bad(pmd))
+			break;
+
+		ptep = pte_offset_map(pmdp, addr);
+		pte = READ_ONCE(*ptep);
+		pr_cont(", pte=%016llx", pte_val(pte));
+		pte_unmap(ptep);
+	} while(0);
+
+	pr_cont("\n");
+}
+
+/*
+ * This function sets the access flags (dirty, accessed), as well as write
+ * permission, and only to a more permissive setting.
+ *
+ * It needs to cope with hardware update of the accessed/dirty state by other
+ * agents in the system and can safely skip the __sync_icache_dcache() call as,
+ * like set_pte_at(), the PTE is never changed from no-exec to exec here.
+ *
+ * Returns whether or not the PTE actually changed.
+ */
+int ptep_set_access_flags(struct vm_area_struct *vma,
+			  unsigned long address, pte_t *ptep,
+			  pte_t entry, int dirty)
+{
+	pteval_t old_pteval, pteval;
+	pte_t pte = READ_ONCE(*ptep);
+
+	if (pte_same(pte, entry))
+		return 0;
+
+	/* only preserve the access flags and write permission */
+	pte_val(entry) &= PTE_RDONLY | PTE_AF | PTE_WRITE | PTE_DIRTY;
+
+	/*
+	 * Setting the flags must be done atomically to avoid racing with the
+	 * hardware update of the access/dirty state. The PTE_RDONLY bit must
+	 * be set to the most permissive (lowest value) of *ptep and entry
+	 * (calculated as: a & b == ~(~a | ~b)).
+	 */
+	pte_val(entry) ^= PTE_RDONLY;
+	pteval = pte_val(pte);
+	do {
+		old_pteval = pteval;
+		pteval ^= PTE_RDONLY;
+		pteval |= pte_val(entry);
+		pteval ^= PTE_RDONLY;
+		pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval);
+	} while (pteval != old_pteval);
+
+	/* Invalidate a stale read-only entry */
+	if (dirty)
+		flush_tlb_page(vma, address);
+	return 1;
+}
+
+static bool is_el1_instruction_abort(unsigned int esr)
+{
+	return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_CUR;
+}
+
+static inline bool is_el1_permission_fault(unsigned long addr, unsigned int esr,
+					   struct pt_regs *regs)
+{
+	unsigned int ec       = ESR_ELx_EC(esr);
+	unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
+
+	if (ec != ESR_ELx_EC_DABT_CUR && ec != ESR_ELx_EC_IABT_CUR)
+		return false;
+
+	if (fsc_type == ESR_ELx_FSC_PERM)
+		return true;
+
+	if (is_ttbr0_addr(addr) && system_uses_ttbr0_pan())
+		return fsc_type == ESR_ELx_FSC_FAULT &&
+			(regs->pstate & PSR_PAN_BIT);
+
+	return false;
+}
+
+static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
+							unsigned int esr,
+							struct pt_regs *regs)
+{
+	unsigned long flags;
+	u64 par, dfsc;
+
+	if (ESR_ELx_EC(esr) != ESR_ELx_EC_DABT_CUR ||
+	    (esr & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT)
+		return false;
+
+	local_irq_save(flags);
+	asm volatile("at s1e1r, %0" :: "r" (addr));
+	isb();
+	par = read_sysreg_par();
+	local_irq_restore(flags);
+
+	/*
+	 * If we now have a valid translation, treat the translation fault as
+	 * spurious.
+	 */
+	if (!(par & SYS_PAR_EL1_F))
+		return true;
+
+	/*
+	 * If we got a different type of fault from the AT instruction,
+	 * treat the translation fault as spurious.
+	 */
+	dfsc = FIELD_GET(SYS_PAR_EL1_FST, par);
+	return (dfsc & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT;
+}
+
+static void die_kernel_fault(const char *msg, unsigned long addr,
+			     unsigned int esr, struct pt_regs *regs)
+{
+	bust_spinlocks(1);
+
+	pr_alert("Unable to handle kernel %s at virtual address %016lx\n", msg,
+		 addr);
+
+	mem_abort_decode(esr);
+
+	show_pte(addr);
+	die("Oops", regs, esr);
+	bust_spinlocks(0);
+	make_task_dead(SIGKILL);
+}
+
+static void __do_kernel_fault(unsigned long addr, unsigned int esr,
+			      struct pt_regs *regs)
+{
+	const char *msg;
+
+	/*
+	 * Are we prepared to handle this kernel fault?
+	 * We are almost certainly not prepared to handle instruction faults.
+	 */
+	if (!is_el1_instruction_abort(esr) && fixup_exception(regs))
+		return;
+
+	if (WARN_RATELIMIT(is_spurious_el1_translation_fault(addr, esr, regs),
+	    "Ignoring spurious kernel translation fault at virtual address %016lx\n", addr))
+		return;
+
+	if (is_el1_permission_fault(addr, esr, regs)) {
+		if (esr & ESR_ELx_WNR)
+			msg = "write to read-only memory";
+		else if (is_el1_instruction_abort(esr))
+			msg = "execute from non-executable memory";
+		else
+			msg = "read from unreadable memory";
+	} else if (addr < PAGE_SIZE) {
+		msg = "NULL pointer dereference";
+	} else {
+		msg = "paging request";
+	}
+
+	die_kernel_fault(msg, addr, esr, regs);
+}
+
+static void set_thread_esr(unsigned long address, unsigned int esr)
+{
+	current->thread.fault_address = address;
+
+	/*
+	 * If the faulting address is in the kernel, we must sanitize the ESR.
+	 * From userspace's point of view, kernel-only mappings don't exist
+	 * at all, so we report them as level 0 translation faults.
+	 * (This is not quite the way that "no mapping there at all" behaves:
+	 * an alignment fault not caused by the memory type would take
+	 * precedence over translation fault for a real access to empty
+	 * space. Unfortunately we can't easily distinguish "alignment fault
+	 * not caused by memory type" from "alignment fault caused by memory
+	 * type", so we ignore this wrinkle and just return the translation
+	 * fault.)
+	 */
+	if (!is_ttbr0_addr(current->thread.fault_address)) {
+		switch (ESR_ELx_EC(esr)) {
+		case ESR_ELx_EC_DABT_LOW:
+			/*
+			 * These bits provide only information about the
+			 * faulting instruction, which userspace knows already.
+			 * We explicitly clear bits which are architecturally
+			 * RES0 in case they are given meanings in future.
+			 * We always report the ESR as if the fault was taken
+			 * to EL1 and so ISV and the bits in ISS[23:14] are
+			 * clear. (In fact it always will be a fault to EL1.)
+			 */
+			esr &= ESR_ELx_EC_MASK | ESR_ELx_IL |
+				ESR_ELx_CM | ESR_ELx_WNR;
+			esr |= ESR_ELx_FSC_FAULT;
+			break;
+		case ESR_ELx_EC_IABT_LOW:
+			/*
+			 * Claim a level 0 translation fault.
+			 * All other bits are architecturally RES0 for faults
+			 * reported with that DFSC value, so we clear them.
+			 */
+			esr &= ESR_ELx_EC_MASK | ESR_ELx_IL;
+			esr |= ESR_ELx_FSC_FAULT;
+			break;
+		default:
+			/*
+			 * This should never happen (entry.S only brings us
+			 * into this code for insn and data aborts from a lower
+			 * exception level). Fail safe by not providing an ESR
+			 * context record at all.
+			 */
+			WARN(1, "ESR 0x%x is not DABT or IABT from EL0\n", esr);
+			esr = 0;
+			break;
+		}
+	}
+
+	current->thread.fault_code = esr;
+}
+
+static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+{
+	/*
+	 * If we are in kernel mode at this point, we have no context to
+	 * handle this fault with.
+	 */
+	if (user_mode(regs)) {
+		const struct fault_info *inf = esr_to_fault_info(esr);
+
+		set_thread_esr(addr, esr);
+		arm64_force_sig_fault(inf->sig, inf->code, (void __user *)addr,
+				      inf->name);
+	} else {
+		__do_kernel_fault(addr, esr, regs);
+	}
+}
+
+#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
+#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+
+static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
+				  unsigned int mm_flags, unsigned long vm_flags,
+				  struct pt_regs *regs)
+{
+	struct vm_area_struct *vma = find_vma(mm, addr);
+
+	if (unlikely(!vma))
+		return VM_FAULT_BADMAP;
+
+	/*
+	 * Ok, we have a good vm_area for this memory access, so we can handle
+	 * it.
+	 */
+	if (unlikely(vma->vm_start > addr)) {
+		if (!(vma->vm_flags & VM_GROWSDOWN))
+			return VM_FAULT_BADMAP;
+		if (expand_stack(vma, addr))
+			return VM_FAULT_BADMAP;
+	}
+
+	/*
+	 * Check that the permissions on the VMA allow for the fault which
+	 * occurred.
+	 */
+	if (!(vma->vm_flags & vm_flags))
+		return VM_FAULT_BADACCESS;
+	return handle_mm_fault(vma, addr & PAGE_MASK, mm_flags, regs);
+}
+
+static bool is_el0_instruction_abort(unsigned int esr)
+{
+	return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_LOW;
+}
+
+/*
+ * Note: not valid for EL1 DC IVAC, but we never use that such that it
+ * should fault. EL0 cannot issue DC IVAC (undef).
+ */
+static bool is_write_abort(unsigned int esr)
+{
+	return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
+}
+
+static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
+				   struct pt_regs *regs)
+{
+	const struct fault_info *inf;
+	struct mm_struct *mm = current->mm;
+	vm_fault_t fault;
+	unsigned long vm_flags = VM_ACCESS_FLAGS;
+	unsigned int mm_flags = FAULT_FLAG_DEFAULT;
+
+	if (kprobe_page_fault(regs, esr))
+		return 0;
+
+	/*
+	 * If we're in an interrupt or have no user context, we must not take
+	 * the fault.
+	 */
+	if (faulthandler_disabled() || !mm)
+		goto no_context;
+
+	if (user_mode(regs))
+		mm_flags |= FAULT_FLAG_USER;
+
+	if (is_el0_instruction_abort(esr)) {
+		vm_flags = VM_EXEC;
+		mm_flags |= FAULT_FLAG_INSTRUCTION;
+	} else if (is_write_abort(esr)) {
+		vm_flags = VM_WRITE;
+		mm_flags |= FAULT_FLAG_WRITE;
+	}
+
+	if (is_ttbr0_addr(addr) && is_el1_permission_fault(addr, esr, regs)) {
+		/* regs->orig_addr_limit may be 0 if we entered from EL0 */
+		if (regs->orig_addr_limit == KERNEL_DS)
+			die_kernel_fault("access to user memory with fs=KERNEL_DS",
+					 addr, esr, regs);
+
+		if (is_el1_instruction_abort(esr))
+			die_kernel_fault("execution of user memory",
+					 addr, esr, regs);
+
+		if (!search_exception_tables(regs->pc))
+			die_kernel_fault("access to user memory outside uaccess routines",
+					 addr, esr, regs);
+	}
+
+	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
+
+	/*
+	 * As per x86, we may deadlock here. However, since the kernel only
+	 * validly references user space from well defined areas of the code,
+	 * we can bug out early if this is from code which shouldn't.
+	 */
+	if (!mmap_read_trylock(mm)) {
+		if (!user_mode(regs) && !search_exception_tables(regs->pc))
+			goto no_context;
+retry:
+		mmap_read_lock(mm);
+	} else {
+		/*
+		 * The above down_read_trylock() might have succeeded in which
+		 * case, we'll have missed the might_sleep() from down_read().
+		 */
+		might_sleep();
+#ifdef CONFIG_DEBUG_VM
+		if (!user_mode(regs) && !search_exception_tables(regs->pc)) {
+			mmap_read_unlock(mm);
+			goto no_context;
+		}
+#endif
+	}
+
+	fault = __do_page_fault(mm, addr, mm_flags, vm_flags, regs);
+
+	/* Quick path to respond to signals */
+	if (fault_signal_pending(fault, regs)) {
+		if (!user_mode(regs))
+			goto no_context;
+		return 0;
+	}
+
+	if (fault & VM_FAULT_RETRY) {
+		if (mm_flags & FAULT_FLAG_ALLOW_RETRY) {
+			mm_flags |= FAULT_FLAG_TRIED;
+			goto retry;
+		}
+	}
+	mmap_read_unlock(mm);
+
+	/*
+	 * Handle the "normal" (no error) case first.
+	 */
+	if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP |
+			      VM_FAULT_BADACCESS))))
+		return 0;
+
+	/*
+	 * If we are in kernel mode at this point, we have no context to
+	 * handle this fault with.
+	 */
+	if (!user_mode(regs))
+		goto no_context;
+
+	if (fault & VM_FAULT_OOM) {
+		/*
+		 * We ran out of memory, call the OOM killer, and return to
+		 * userspace (which will retry the fault, or kill us if we got
+		 * oom-killed).
+		 */
+		pagefault_out_of_memory();
+		return 0;
+	}
+
+	inf = esr_to_fault_info(esr);
+	set_thread_esr(addr, esr);
+	if (fault & VM_FAULT_SIGBUS) {
+		/*
+		 * We had some memory, but were unable to successfully fix up
+		 * this page fault.
+		 */
+		arm64_force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)addr,
+				      inf->name);
+	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
+		unsigned int lsb;
+
+		lsb = PAGE_SHIFT;
+		if (fault & VM_FAULT_HWPOISON_LARGE)
+			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
+
+		arm64_force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, lsb,
+				       inf->name);
+	} else {
+		/*
+		 * Something tried to access memory that isn't in our memory
+		 * map.
+		 */
+		arm64_force_sig_fault(SIGSEGV,
+				      fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR,
+				      (void __user *)addr,
+				      inf->name);
+	}
+
+	return 0;
+
+no_context:
+	__do_kernel_fault(addr, esr, regs);
+	return 0;
+}
+
+static int __kprobes do_translation_fault(unsigned long addr,
+					  unsigned int esr,
+					  struct pt_regs *regs)
+{
+	if (is_ttbr0_addr(addr))
+		return do_page_fault(addr, esr, regs);
+
+	do_bad_area(addr, esr, regs);
+	return 0;
+}
+
+static int do_alignment_fault(unsigned long addr, unsigned int esr,
+			      struct pt_regs *regs)
+{
+	do_bad_area(addr, esr, regs);
+	return 0;
+}
+
+static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+{
+	return 1; /* "fault" */
+}
+
+static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+{
+	const struct fault_info *inf;
+	void __user *siaddr;
+
+	inf = esr_to_fault_info(esr);
+
+	if (user_mode(regs) && apei_claim_sea(regs) == 0) {
+		/*
+		 * APEI claimed this as a firmware-first notification.
+		 * Some processing deferred to task_work before ret_to_user().
+		 */
+		return 0;
+	}
+
+	if (esr & ESR_ELx_FnV)
+		siaddr = NULL;
+	else
+		siaddr  = (void __user *)addr;
+	arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
+
+	return 0;
+}
+
+static int do_tag_check_fault(unsigned long addr, unsigned int esr,
+			      struct pt_regs *regs)
+{
+	do_bad_area(addr, esr, regs);
+	return 0;
+}
+
+static const struct fault_info fault_info[] = {
+	{ do_bad,		SIGKILL, SI_KERNEL,	"ttbr address size fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"level 1 address size fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"level 2 address size fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"level 3 address size fault"	},
+	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 0 translation fault"	},
+	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 1 translation fault"	},
+	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 2 translation fault"	},
+	{ do_translation_fault,	SIGSEGV, SEGV_MAPERR,	"level 3 translation fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 8"			},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 access flag fault"	},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 access flag fault"	},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 access flag fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 12"			},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 1 permission fault"	},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 2 permission fault"	},
+	{ do_page_fault,	SIGSEGV, SEGV_ACCERR,	"level 3 permission fault"	},
+	{ do_sea,		SIGBUS,  BUS_OBJERR,	"synchronous external abort"	},
+	{ do_tag_check_fault,	SIGSEGV, SEGV_MTESERR,	"synchronous tag check fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 18"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 19"			},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 0 (translation table walk)"	},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 1 (translation table walk)"	},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 2 (translation table walk)"	},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 3 (translation table walk)"	},
+	{ do_sea,		SIGBUS,  BUS_OBJERR,	"synchronous parity or ECC error" },	// Reserved when RAS is implemented
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 25"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 26"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 27"			},
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 0 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 1 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 2 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
+	{ do_sea,		SIGKILL, SI_KERNEL,	"level 3 synchronous parity error (translation table walk)"	},	// Reserved when RAS is implemented
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 32"			},
+	{ do_alignment_fault,	SIGBUS,  BUS_ADRALN,	"alignment fault"		},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 34"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 35"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 36"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 37"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 38"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 39"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 40"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 41"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 42"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 43"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 44"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 45"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 46"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 47"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"TLB conflict abort"		},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"Unsupported atomic hardware update fault"	},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 50"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 51"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"implementation fault (lockdown abort)" },
+	{ do_bad,		SIGBUS,  BUS_OBJERR,	"implementation fault (unsupported exclusive)" },
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 54"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 55"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 56"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 57"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 58" 			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 59"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 60"			},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"section domain fault"		},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"page domain fault"		},
+	{ do_bad,		SIGKILL, SI_KERNEL,	"unknown 63"			},
+};
+
+void do_mem_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+{
+	const struct fault_info *inf = esr_to_fault_info(esr);
+
+	if (!inf->fn(addr, esr, regs))
+		return;
+
+	if (!user_mode(regs)) {
+		pr_alert("Unhandled fault at 0x%016lx\n", addr);
+		mem_abort_decode(esr);
+		show_pte(addr);
+	}
+
+	arm64_notify_die(inf->name, regs,
+			 inf->sig, inf->code, (void __user *)addr, esr);
+}
+NOKPROBE_SYMBOL(do_mem_abort);
+
+void do_el0_irq_bp_hardening(void)
+{
+	/* PC has already been checked in entry.S */
+	arm64_apply_bp_hardening();
+}
+NOKPROBE_SYMBOL(do_el0_irq_bp_hardening);
+
+void do_sp_pc_abort(unsigned long addr, unsigned int esr, struct pt_regs *regs)
+{
+	arm64_notify_die("SP/PC alignment exception", regs,
+			 SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
+}
+NOKPROBE_SYMBOL(do_sp_pc_abort);
+
+int __init early_brk64(unsigned long addr, unsigned int esr,
+		       struct pt_regs *regs);
+
+/*
+ * __refdata because early_brk64 is __init, but the reference to it is
+ * clobbered at arch_initcall time.
+ * See traps.c and debug-monitors.c:debug_traps_init().
+ */
+static struct fault_info __refdata debug_fault_info[] = {
+	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware breakpoint"	},
+	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware single-step"	},
+	{ do_bad,	SIGTRAP,	TRAP_HWBKPT,	"hardware watchpoint"	},
+	{ do_bad,	SIGKILL,	SI_KERNEL,	"unknown 3"		},
+	{ do_bad,	SIGTRAP,	TRAP_BRKPT,	"aarch32 BKPT"		},
+	{ do_bad,	SIGKILL,	SI_KERNEL,	"aarch32 vector catch"	},
+	{ early_brk64,	SIGTRAP,	TRAP_BRKPT,	"aarch64 BRK"		},
+	{ do_bad,	SIGKILL,	SI_KERNEL,	"unknown 7"		},
+};
+
+void __init hook_debug_fault_code(int nr,
+				  int (*fn)(unsigned long, unsigned int, struct pt_regs *),
+				  int sig, int code, const char *name)
+{
+	BUG_ON(nr < 0 || nr >= ARRAY_SIZE(debug_fault_info));
+
+	debug_fault_info[nr].fn		= fn;
+	debug_fault_info[nr].sig	= sig;
+	debug_fault_info[nr].code	= code;
+	debug_fault_info[nr].name	= name;
+}
+
+/*
+ * In debug exception context, we explicitly disable preemption despite
+ * having interrupts disabled.
+ * This serves two purposes: it makes it much less likely that we would
+ * accidentally schedule in exception context and it will force a warning
+ * if we somehow manage to schedule by accident.
+ */
+static void debug_exception_enter(struct pt_regs *regs)
+{
+	preempt_disable();
+
+	/* This code is a bit fragile.  Test it. */
+	RCU_LOCKDEP_WARN(!rcu_is_watching(), "exception_enter didn't work");
+}
+NOKPROBE_SYMBOL(debug_exception_enter);
+
+static void debug_exception_exit(struct pt_regs *regs)
+{
+	preempt_enable_no_resched();
+}
+NOKPROBE_SYMBOL(debug_exception_exit);
+
+#ifdef CONFIG_ARM64_ERRATUM_1463225
+DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
+
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+{
+	if (user_mode(regs))
+		return 0;
+
+	if (!__this_cpu_read(__in_cortex_a76_erratum_1463225_wa))
+		return 0;
+
+	/*
+	 * We've taken a dummy step exception from the kernel to ensure
+	 * that interrupts are re-enabled on the syscall path. Return back
+	 * to cortex_a76_erratum_1463225_svc_handler() with debug exceptions
+	 * masked so that we can safely restore the mdscr and get on with
+	 * handling the syscall.
+	 */
+	regs->pstate |= PSR_D_BIT;
+	return 1;
+}
+#else
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+{
+	return 0;
+}
+#endif /* CONFIG_ARM64_ERRATUM_1463225 */
+NOKPROBE_SYMBOL(cortex_a76_erratum_1463225_debug_handler);
+
+void do_debug_exception(unsigned long addr_if_watchpoint, unsigned int esr,
+			struct pt_regs *regs)
+{
+	const struct fault_info *inf = esr_to_debug_fault_info(esr);
+	unsigned long pc = instruction_pointer(regs);
+
+	if (cortex_a76_erratum_1463225_debug_handler(regs))
+		return;
+
+	debug_exception_enter(regs);
+
+	if (user_mode(regs) && !is_ttbr0_addr(pc))
+		arm64_apply_bp_hardening();
+
+	if (inf->fn(addr_if_watchpoint, esr, regs)) {
+		arm64_notify_die(inf->name, regs,
+				 inf->sig, inf->code, (void __user *)pc, esr);
+	}
+
+	debug_exception_exit(regs);
+}
+NOKPROBE_SYMBOL(do_debug_exception);
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
new file mode 100644
index 000000000..6d44c028d
--- /dev/null
+++ b/arch/arm64/mm/flush.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/flush.c
+ *
+ * Copyright (C) 1995-2002 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cache.h>
+#include <asm/tlbflush.h>
+
+void sync_icache_aliases(void *kaddr, unsigned long len)
+{
+	unsigned long addr = (unsigned long)kaddr;
+
+	if (icache_is_aliasing()) {
+		__clean_dcache_area_pou(kaddr, len);
+		__flush_icache_all();
+	} else {
+		/*
+		 * Don't issue kick_all_cpus_sync() after I-cache invalidation
+		 * for user mappings.
+		 */
+		__flush_icache_range(addr, addr + len);
+	}
+}
+
+static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
+				unsigned long uaddr, void *kaddr,
+				unsigned long len)
+{
+	if (vma->vm_flags & VM_EXEC)
+		sync_icache_aliases(kaddr, len);
+}
+
+/*
+ * Copy user data from/to a page which is mapped into a different processes
+ * address space.  Really, we want to allow our "user space" model to handle
+ * this.
+ */
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+		       unsigned long uaddr, void *dst, const void *src,
+		       unsigned long len)
+{
+	memcpy(dst, src, len);
+	flush_ptrace_access(vma, page, uaddr, dst, len);
+}
+
+void __sync_icache_dcache(pte_t pte)
+{
+	struct page *page = pte_page(pte);
+
+	if (!test_bit(PG_dcache_clean, &page->flags)) {
+		sync_icache_aliases(page_address(page), page_size(page));
+		set_bit(PG_dcache_clean, &page->flags);
+	}
+}
+EXPORT_SYMBOL_GPL(__sync_icache_dcache);
+
+/*
+ * This function is called when a page has been modified by the kernel. Mark
+ * it as dirty for later flushing when mapped in user space (if executable,
+ * see __sync_icache_dcache).
+ */
+void flush_dcache_page(struct page *page)
+{
+	if (test_bit(PG_dcache_clean, &page->flags))
+		clear_bit(PG_dcache_clean, &page->flags);
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+/*
+ * Additional functions defined in assembly.
+ */
+EXPORT_SYMBOL(__flush_icache_range);
+
+#ifdef CONFIG_ARCH_HAS_PMEM_API
+void arch_wb_cache_pmem(void *addr, size_t size)
+{
+	/* Ensure order against any prior non-cacheable writes */
+	dmb(osh);
+	__clean_dcache_area_pop(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+	__inval_dcache_area(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
+#endif
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
new file mode 100644
index 000000000..99cd6e718
--- /dev/null
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -0,0 +1,518 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch/arm64/mm/hugetlbpage.c
+ *
+ * Copyright (C) 2013 Linaro Ltd.
+ *
+ * Based on arch/x86/mm/hugetlbpage.c.
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/err.h>
+#include <linux/sysctl.h>
+#include <asm/mman.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+
+/*
+ * HugeTLB Support Matrix
+ *
+ * ---------------------------------------------------
+ * | Page Size | CONT PTE |  PMD  | CONT PMD |  PUD  |
+ * ---------------------------------------------------
+ * |     4K    |   64K    |   2M  |    32M   |   1G  |
+ * |    16K    |    2M    |  32M  |     1G   |       |
+ * |    64K    |    2M    | 512M  |    16G   |       |
+ * ---------------------------------------------------
+ */
+
+/*
+ * Reserve CMA areas for the largest supported gigantic
+ * huge page when requested. Any other smaller gigantic
+ * huge pages could still be served from those areas.
+ */
+#ifdef CONFIG_CMA
+void __init arm64_hugetlb_cma_reserve(void)
+{
+	int order;
+
+#ifdef CONFIG_ARM64_4K_PAGES
+	order = PUD_SHIFT - PAGE_SHIFT;
+#else
+	order = CONT_PMD_SHIFT - PAGE_SHIFT;
+#endif
+	/*
+	 * HugeTLB CMA reservation is required for gigantic
+	 * huge pages which could not be allocated via the
+	 * page allocator. Just warn if there is any change
+	 * breaking this assumption.
+	 */
+	WARN_ON(order <= MAX_ORDER);
+	hugetlb_cma_reserve(order);
+}
+#endif /* CONFIG_CMA */
+
+#ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION
+bool arch_hugetlb_migration_supported(struct hstate *h)
+{
+	size_t pagesize = huge_page_size(h);
+
+	switch (pagesize) {
+#ifdef CONFIG_ARM64_4K_PAGES
+	case PUD_SIZE:
+#endif
+	case PMD_SIZE:
+	case CONT_PMD_SIZE:
+	case CONT_PTE_SIZE:
+		return true;
+	}
+	pr_warn("%s: unrecognized huge page size 0x%lx\n",
+			__func__, pagesize);
+	return false;
+}
+#endif
+
+int pmd_huge(pmd_t pmd)
+{
+	return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
+}
+
+int pud_huge(pud_t pud)
+{
+#ifndef __PAGETABLE_PMD_FOLDED
+	return pud_val(pud) && !(pud_val(pud) & PUD_TABLE_BIT);
+#else
+	return 0;
+#endif
+}
+
+/*
+ * Select all bits except the pfn
+ */
+static inline pgprot_t pte_pgprot(pte_t pte)
+{
+	unsigned long pfn = pte_pfn(pte);
+
+	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
+}
+
+static int find_num_contig(struct mm_struct *mm, unsigned long addr,
+			   pte_t *ptep, size_t *pgsize)
+{
+	pgd_t *pgdp = pgd_offset(mm, addr);
+	p4d_t *p4dp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+
+	*pgsize = PAGE_SIZE;
+	p4dp = p4d_offset(pgdp, addr);
+	pudp = pud_offset(p4dp, addr);
+	pmdp = pmd_offset(pudp, addr);
+	if ((pte_t *)pmdp == ptep) {
+		*pgsize = PMD_SIZE;
+		return CONT_PMDS;
+	}
+	return CONT_PTES;
+}
+
+static inline int num_contig_ptes(unsigned long size, size_t *pgsize)
+{
+	int contig_ptes = 0;
+
+	*pgsize = size;
+
+	switch (size) {
+#ifdef CONFIG_ARM64_4K_PAGES
+	case PUD_SIZE:
+#endif
+	case PMD_SIZE:
+		contig_ptes = 1;
+		break;
+	case CONT_PMD_SIZE:
+		*pgsize = PMD_SIZE;
+		contig_ptes = CONT_PMDS;
+		break;
+	case CONT_PTE_SIZE:
+		*pgsize = PAGE_SIZE;
+		contig_ptes = CONT_PTES;
+		break;
+	}
+
+	return contig_ptes;
+}
+
+/*
+ * Changing some bits of contiguous entries requires us to follow a
+ * Break-Before-Make approach, breaking the whole contiguous set
+ * before we can change any entries. See ARM DDI 0487A.k_iss10775,
+ * "Misprogramming of the Contiguous bit", page D4-1762.
+ *
+ * This helper performs the break step.
+ */
+static pte_t get_clear_flush(struct mm_struct *mm,
+			     unsigned long addr,
+			     pte_t *ptep,
+			     unsigned long pgsize,
+			     unsigned long ncontig)
+{
+	pte_t orig_pte = huge_ptep_get(ptep);
+	bool valid = pte_valid(orig_pte);
+	unsigned long i, saddr = addr;
+
+	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
+		pte_t pte = ptep_get_and_clear(mm, addr, ptep);
+
+		/*
+		 * If HW_AFDBM is enabled, then the HW could turn on
+		 * the dirty or accessed bit for any page in the set,
+		 * so check them all.
+		 */
+		if (pte_dirty(pte))
+			orig_pte = pte_mkdirty(orig_pte);
+
+		if (pte_young(pte))
+			orig_pte = pte_mkyoung(orig_pte);
+	}
+
+	if (valid) {
+		struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
+		flush_tlb_range(&vma, saddr, addr);
+	}
+	return orig_pte;
+}
+
+/*
+ * Changing some bits of contiguous entries requires us to follow a
+ * Break-Before-Make approach, breaking the whole contiguous set
+ * before we can change any entries. See ARM DDI 0487A.k_iss10775,
+ * "Misprogramming of the Contiguous bit", page D4-1762.
+ *
+ * This helper performs the break step for use cases where the
+ * original pte is not needed.
+ */
+static void clear_flush(struct mm_struct *mm,
+			     unsigned long addr,
+			     pte_t *ptep,
+			     unsigned long pgsize,
+			     unsigned long ncontig)
+{
+	struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
+	unsigned long i, saddr = addr;
+
+	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
+		pte_clear(mm, addr, ptep);
+
+	flush_tlb_range(&vma, saddr, addr);
+}
+
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+			    pte_t *ptep, pte_t pte)
+{
+	size_t pgsize;
+	int i;
+	int ncontig;
+	unsigned long pfn, dpfn;
+	pgprot_t hugeprot;
+
+	/*
+	 * Code needs to be expanded to handle huge swap and migration
+	 * entries. Needed for HUGETLB and MEMORY_FAILURE.
+	 */
+	WARN_ON(!pte_present(pte));
+
+	if (!pte_cont(pte)) {
+		set_pte_at(mm, addr, ptep, pte);
+		return;
+	}
+
+	ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+	pfn = pte_pfn(pte);
+	dpfn = pgsize >> PAGE_SHIFT;
+	hugeprot = pte_pgprot(pte);
+
+	clear_flush(mm, addr, ptep, pgsize, ncontig);
+
+	for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
+		set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+}
+
+void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
+			  pte_t *ptep, pte_t pte, unsigned long sz)
+{
+	int i, ncontig;
+	size_t pgsize;
+
+	ncontig = num_contig_ptes(sz, &pgsize);
+
+	for (i = 0; i < ncontig; i++, ptep++)
+		set_pte(ptep, pte);
+}
+
+pte_t *huge_pte_alloc(struct mm_struct *mm,
+		      unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+	pte_t *ptep = NULL;
+
+	pgdp = pgd_offset(mm, addr);
+	p4dp = p4d_offset(pgdp, addr);
+	pudp = pud_alloc(mm, p4dp, addr);
+	if (!pudp)
+		return NULL;
+
+	if (sz == PUD_SIZE) {
+		ptep = (pte_t *)pudp;
+	} else if (sz == (CONT_PTE_SIZE)) {
+		pmdp = pmd_alloc(mm, pudp, addr);
+		if (!pmdp)
+			return NULL;
+
+		WARN_ON(addr & (sz - 1));
+		/*
+		 * Note that if this code were ever ported to the
+		 * 32-bit arm platform then it will cause trouble in
+		 * the case where CONFIG_HIGHPTE is set, since there
+		 * will be no pte_unmap() to correspond with this
+		 * pte_alloc_map().
+		 */
+		ptep = pte_alloc_map(mm, pmdp, addr);
+	} else if (sz == PMD_SIZE) {
+		if (IS_ENABLED(CONFIG_ARCH_WANT_HUGE_PMD_SHARE) &&
+		    pud_none(READ_ONCE(*pudp)))
+			ptep = huge_pmd_share(mm, addr, pudp);
+		else
+			ptep = (pte_t *)pmd_alloc(mm, pudp, addr);
+	} else if (sz == (CONT_PMD_SIZE)) {
+		pmdp = pmd_alloc(mm, pudp, addr);
+		WARN_ON(addr & (sz - 1));
+		return (pte_t *)pmdp;
+	}
+
+	return ptep;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm,
+		       unsigned long addr, unsigned long sz)
+{
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp, pud;
+	pmd_t *pmdp, pmd;
+
+	pgdp = pgd_offset(mm, addr);
+	if (!pgd_present(READ_ONCE(*pgdp)))
+		return NULL;
+
+	p4dp = p4d_offset(pgdp, addr);
+	if (!p4d_present(READ_ONCE(*p4dp)))
+		return NULL;
+
+	pudp = pud_offset(p4dp, addr);
+	pud = READ_ONCE(*pudp);
+	if (sz != PUD_SIZE && pud_none(pud))
+		return NULL;
+	/* hugepage or swap? */
+	if (pud_huge(pud) || !pud_present(pud))
+		return (pte_t *)pudp;
+	/* table; check the next level */
+
+	if (sz == CONT_PMD_SIZE)
+		addr &= CONT_PMD_MASK;
+
+	pmdp = pmd_offset(pudp, addr);
+	pmd = READ_ONCE(*pmdp);
+	if (!(sz == PMD_SIZE || sz == CONT_PMD_SIZE) &&
+	    pmd_none(pmd))
+		return NULL;
+	if (pmd_huge(pmd) || !pmd_present(pmd))
+		return (pte_t *)pmdp;
+
+	if (sz == CONT_PTE_SIZE)
+		return pte_offset_kernel(pmdp, (addr & CONT_PTE_MASK));
+
+	return NULL;
+}
+
+pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
+			 struct page *page, int writable)
+{
+	size_t pagesize = huge_page_size(hstate_vma(vma));
+
+	if (pagesize == CONT_PTE_SIZE) {
+		entry = pte_mkcont(entry);
+	} else if (pagesize == CONT_PMD_SIZE) {
+		entry = pmd_pte(pmd_mkcont(pte_pmd(entry)));
+	} else if (pagesize != PUD_SIZE && pagesize != PMD_SIZE) {
+		pr_warn("%s: unrecognized huge page size 0x%lx\n",
+			__func__, pagesize);
+	}
+	return entry;
+}
+
+void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+		    pte_t *ptep, unsigned long sz)
+{
+	int i, ncontig;
+	size_t pgsize;
+
+	ncontig = num_contig_ptes(sz, &pgsize);
+
+	for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
+		pte_clear(mm, addr, ptep);
+}
+
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
+			      unsigned long addr, pte_t *ptep)
+{
+	int ncontig;
+	size_t pgsize;
+	pte_t orig_pte = huge_ptep_get(ptep);
+
+	if (!pte_cont(orig_pte))
+		return ptep_get_and_clear(mm, addr, ptep);
+
+	ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+
+	return get_clear_flush(mm, addr, ptep, pgsize, ncontig);
+}
+
+/*
+ * huge_ptep_set_access_flags will update access flags (dirty, accesssed)
+ * and write permission.
+ *
+ * For a contiguous huge pte range we need to check whether or not write
+ * permission has to change only on the first pte in the set. Then for
+ * all the contiguous ptes we need to check whether or not there is a
+ * discrepancy between dirty or young.
+ */
+static int __cont_access_flags_changed(pte_t *ptep, pte_t pte, int ncontig)
+{
+	int i;
+
+	if (pte_write(pte) != pte_write(huge_ptep_get(ptep)))
+		return 1;
+
+	for (i = 0; i < ncontig; i++) {
+		pte_t orig_pte = huge_ptep_get(ptep + i);
+
+		if (pte_dirty(pte) != pte_dirty(orig_pte))
+			return 1;
+
+		if (pte_young(pte) != pte_young(orig_pte))
+			return 1;
+	}
+
+	return 0;
+}
+
+int huge_ptep_set_access_flags(struct vm_area_struct *vma,
+			       unsigned long addr, pte_t *ptep,
+			       pte_t pte, int dirty)
+{
+	int ncontig, i;
+	size_t pgsize = 0;
+	unsigned long pfn = pte_pfn(pte), dpfn;
+	pgprot_t hugeprot;
+	pte_t orig_pte;
+
+	if (!pte_cont(pte))
+		return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+
+	ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
+	dpfn = pgsize >> PAGE_SHIFT;
+
+	if (!__cont_access_flags_changed(ptep, pte, ncontig))
+		return 0;
+
+	orig_pte = get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
+
+	/* Make sure we don't lose the dirty or young state */
+	if (pte_dirty(orig_pte))
+		pte = pte_mkdirty(pte);
+
+	if (pte_young(orig_pte))
+		pte = pte_mkyoung(pte);
+
+	hugeprot = pte_pgprot(pte);
+	for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
+		set_pte_at(vma->vm_mm, addr, ptep, pfn_pte(pfn, hugeprot));
+
+	return 1;
+}
+
+void huge_ptep_set_wrprotect(struct mm_struct *mm,
+			     unsigned long addr, pte_t *ptep)
+{
+	unsigned long pfn, dpfn;
+	pgprot_t hugeprot;
+	int ncontig, i;
+	size_t pgsize;
+	pte_t pte;
+
+	if (!pte_cont(READ_ONCE(*ptep))) {
+		ptep_set_wrprotect(mm, addr, ptep);
+		return;
+	}
+
+	ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+	dpfn = pgsize >> PAGE_SHIFT;
+
+	pte = get_clear_flush(mm, addr, ptep, pgsize, ncontig);
+	pte = pte_wrprotect(pte);
+
+	hugeprot = pte_pgprot(pte);
+	pfn = pte_pfn(pte);
+
+	for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
+		set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+}
+
+void huge_ptep_clear_flush(struct vm_area_struct *vma,
+			   unsigned long addr, pte_t *ptep)
+{
+	size_t pgsize;
+	int ncontig;
+
+	if (!pte_cont(READ_ONCE(*ptep))) {
+		ptep_clear_flush(vma, addr, ptep);
+		return;
+	}
+
+	ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
+	clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
+}
+
+static int __init hugetlbpage_init(void)
+{
+#ifdef CONFIG_ARM64_4K_PAGES
+	hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+#endif
+	hugetlb_add_hstate(CONT_PMD_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(CONT_PTE_SHIFT - PAGE_SHIFT);
+
+	return 0;
+}
+arch_initcall(hugetlbpage_init);
+
+bool __init arch_hugetlb_valid_size(unsigned long size)
+{
+	switch (size) {
+#ifdef CONFIG_ARM64_4K_PAGES
+	case PUD_SIZE:
+#endif
+	case CONT_PMD_SIZE:
+	case PMD_SIZE:
+	case CONT_PTE_SIZE:
+		return true;
+	}
+
+	return false;
+}
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
new file mode 100644
index 000000000..80cc79760
--- /dev/null
+++ b/arch/arm64/mm/init.c
@@ -0,0 +1,613 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/init.c
+ *
+ * Copyright (C) 1995-2005 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/errno.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/cache.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/initrd.h>
+#include <linux/gfp.h>
+#include <linux/memblock.h>
+#include <linux/sort.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/dma-direct.h>
+#include <linux/dma-map-ops.h>
+#include <linux/efi.h>
+#include <linux/swiotlb.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/kexec.h>
+#include <linux/crash_dump.h>
+#include <linux/hugetlb.h>
+#include <linux/acpi_iort.h>
+
+#include <asm/boot.h>
+#include <asm/fixmap.h>
+#include <asm/kasan.h>
+#include <asm/kernel-pgtable.h>
+#include <asm/memory.h>
+#include <asm/numa.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <linux/sizes.h>
+#include <asm/tlb.h>
+#include <asm/alternative.h>
+
+/*
+ * We need to be able to catch inadvertent references to memstart_addr
+ * that occur (potentially in generic code) before arm64_memblock_init()
+ * executes, which assigns it its actual value. So use a default value
+ * that cannot be mistaken for a real physical address.
+ */
+s64 memstart_addr __ro_after_init = -1;
+EXPORT_SYMBOL(memstart_addr);
+
+/*
+ * If the corresponding config options are enabled, we create both ZONE_DMA
+ * and ZONE_DMA32. By default ZONE_DMA covers the 32-bit addressable memory
+ * unless restricted on specific platforms (e.g. 30-bit on Raspberry Pi 4).
+ * In such case, ZONE_DMA32 covers the rest of the 32-bit addressable memory,
+ * otherwise it is empty.
+ *
+ * Memory reservation for crash kernel either done early or deferred
+ * depending on DMA memory zones configs (ZONE_DMA) --
+ *
+ * In absence of ZONE_DMA configs arm64_dma_phys_limit initialized
+ * here instead of max_zone_phys().  This lets early reservation of
+ * crash kernel memory which has a dependency on arm64_dma_phys_limit.
+ * Reserving memory early for crash kernel allows linear creation of block
+ * mappings (greater than page-granularity) for all the memory bank rangs.
+ * In this scheme a comparatively quicker boot is observed.
+ *
+ * If ZONE_DMA configs are defined, crash kernel memory reservation
+ * is delayed until DMA zone memory range size initilazation performed in
+ * zone_sizes_init().  The defer is necessary to steer clear of DMA zone
+ * memory range to avoid overlap allocation.  So crash kernel memory boundaries
+ * are not known when mapping all bank memory ranges, which otherwise means
+ * not possible to exclude crash kernel range from creating block mappings
+ * so page-granularity mappings are created for the entire memory range.
+ * Hence a slightly slower boot is observed.
+ *
+ * Note: Page-granularity mapppings are necessary for crash kernel memory
+ * range for shrinking its size via /sys/kernel/kexec_crash_size interface.
+ */
+#if IS_ENABLED(CONFIG_ZONE_DMA) || IS_ENABLED(CONFIG_ZONE_DMA32)
+phys_addr_t __ro_after_init arm64_dma_phys_limit;
+#else
+phys_addr_t __ro_after_init arm64_dma_phys_limit = PHYS_MASK + 1;
+#endif
+
+#ifdef CONFIG_KEXEC_CORE
+/*
+ * reserve_crashkernel() - reserves memory for crash kernel
+ *
+ * This function reserves memory area given in "crashkernel=" kernel command
+ * line parameter. The memory reserved is used by dump capture kernel when
+ * primary kernel is crashing.
+ */
+static void __init reserve_crashkernel(void)
+{
+	unsigned long long crash_base, crash_size;
+	int ret;
+
+	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
+				&crash_size, &crash_base);
+	/* no crashkernel= or invalid value specified */
+	if (ret || !crash_size)
+		return;
+
+	crash_size = PAGE_ALIGN(crash_size);
+
+	if (crash_base == 0) {
+		/* Current arm64 boot protocol requires 2MB alignment */
+		crash_base = memblock_find_in_range(0, arm64_dma_phys_limit,
+				crash_size, SZ_2M);
+		if (crash_base == 0) {
+			pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
+				crash_size);
+			return;
+		}
+	} else {
+		/* User specifies base address explicitly. */
+		if (!memblock_is_region_memory(crash_base, crash_size)) {
+			pr_warn("cannot reserve crashkernel: region is not memory\n");
+			return;
+		}
+
+		if (memblock_is_region_reserved(crash_base, crash_size)) {
+			pr_warn("cannot reserve crashkernel: region overlaps reserved memory\n");
+			return;
+		}
+
+		if (!IS_ALIGNED(crash_base, SZ_2M)) {
+			pr_warn("cannot reserve crashkernel: base address is not 2MB aligned\n");
+			return;
+		}
+	}
+	memblock_reserve(crash_base, crash_size);
+
+	pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
+		crash_base, crash_base + crash_size, crash_size >> 20);
+
+	crashk_res.start = crash_base;
+	crashk_res.end = crash_base + crash_size - 1;
+}
+#else
+static void __init reserve_crashkernel(void)
+{
+}
+#endif /* CONFIG_KEXEC_CORE */
+
+#ifdef CONFIG_CRASH_DUMP
+static int __init early_init_dt_scan_elfcorehdr(unsigned long node,
+		const char *uname, int depth, void *data)
+{
+	const __be32 *reg;
+	int len;
+
+	if (depth != 1 || strcmp(uname, "chosen") != 0)
+		return 0;
+
+	reg = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
+	if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells)))
+		return 1;
+
+	elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &reg);
+	elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, &reg);
+
+	return 1;
+}
+
+/*
+ * reserve_elfcorehdr() - reserves memory for elf core header
+ *
+ * This function reserves the memory occupied by an elf core header
+ * described in the device tree. This region contains all the
+ * information about primary kernel's core image and is used by a dump
+ * capture kernel to access the system memory on primary kernel.
+ */
+static void __init reserve_elfcorehdr(void)
+{
+	of_scan_flat_dt(early_init_dt_scan_elfcorehdr, NULL);
+
+	if (!elfcorehdr_size)
+		return;
+
+	if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) {
+		pr_warn("elfcorehdr is overlapped\n");
+		return;
+	}
+
+	memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
+
+	pr_info("Reserving %lldKB of memory at 0x%llx for elfcorehdr\n",
+		elfcorehdr_size >> 10, elfcorehdr_addr);
+}
+#else
+static void __init reserve_elfcorehdr(void)
+{
+}
+#endif /* CONFIG_CRASH_DUMP */
+
+/*
+ * Return the maximum physical address for a zone accessible by the given bits
+ * limit. If DRAM starts above 32-bit, expand the zone to the maximum
+ * available memory, otherwise cap it at 32-bit.
+ */
+static phys_addr_t __init max_zone_phys(unsigned int zone_bits)
+{
+	phys_addr_t zone_mask = DMA_BIT_MASK(zone_bits);
+	phys_addr_t phys_start = memblock_start_of_DRAM();
+
+	if (phys_start > U32_MAX)
+		zone_mask = PHYS_ADDR_MAX;
+	else if (phys_start > zone_mask)
+		zone_mask = U32_MAX;
+
+	return min(zone_mask, memblock_end_of_DRAM() - 1) + 1;
+}
+
+static void __init zone_sizes_init(unsigned long min, unsigned long max)
+{
+	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
+	unsigned int __maybe_unused acpi_zone_dma_bits;
+	unsigned int __maybe_unused dt_zone_dma_bits;
+	phys_addr_t __maybe_unused dma32_phys_limit = max_zone_phys(32);
+
+#ifdef CONFIG_ZONE_DMA
+	acpi_zone_dma_bits = fls64(acpi_iort_dma_get_max_cpu_address());
+	dt_zone_dma_bits = fls64(of_dma_get_max_cpu_address(NULL));
+	zone_dma_bits = min3(32U, dt_zone_dma_bits, acpi_zone_dma_bits);
+	arm64_dma_phys_limit = max_zone_phys(zone_dma_bits);
+	max_zone_pfns[ZONE_DMA] = PFN_DOWN(arm64_dma_phys_limit);
+#endif
+#ifdef CONFIG_ZONE_DMA32
+	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
+	if (!arm64_dma_phys_limit)
+		arm64_dma_phys_limit = dma32_phys_limit;
+#endif
+	max_zone_pfns[ZONE_NORMAL] = max;
+
+	free_area_init(max_zone_pfns);
+}
+
+int pfn_valid(unsigned long pfn)
+{
+	phys_addr_t addr = pfn << PAGE_SHIFT;
+
+	if ((addr >> PAGE_SHIFT) != pfn)
+		return 0;
+
+#ifdef CONFIG_SPARSEMEM
+	if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
+		return 0;
+
+	if (!valid_section(__pfn_to_section(pfn)))
+		return 0;
+
+	/*
+	 * ZONE_DEVICE memory does not have the memblock entries.
+	 * memblock_is_map_memory() check for ZONE_DEVICE based
+	 * addresses will always fail. Even the normal hotplugged
+	 * memory will never have MEMBLOCK_NOMAP flag set in their
+	 * memblock entries. Skip memblock search for all non early
+	 * memory sections covering all of hotplug memory including
+	 * both normal and ZONE_DEVICE based.
+	 */
+	if (!early_section(__pfn_to_section(pfn)))
+		return pfn_section_valid(__pfn_to_section(pfn), pfn);
+#endif
+	return memblock_is_map_memory(addr);
+}
+EXPORT_SYMBOL(pfn_valid);
+
+static phys_addr_t memory_limit = PHYS_ADDR_MAX;
+
+/*
+ * Limit the memory size that was specified via FDT.
+ */
+static int __init early_mem(char *p)
+{
+	if (!p)
+		return 1;
+
+	memory_limit = memparse(p, &p) & PAGE_MASK;
+	pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
+
+	return 0;
+}
+early_param("mem", early_mem);
+
+static int __init early_init_dt_scan_usablemem(unsigned long node,
+		const char *uname, int depth, void *data)
+{
+	struct memblock_region *usablemem = data;
+	const __be32 *reg;
+	int len;
+
+	if (depth != 1 || strcmp(uname, "chosen") != 0)
+		return 0;
+
+	reg = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
+	if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells)))
+		return 1;
+
+	usablemem->base = dt_mem_next_cell(dt_root_addr_cells, &reg);
+	usablemem->size = dt_mem_next_cell(dt_root_size_cells, &reg);
+
+	return 1;
+}
+
+static void __init fdt_enforce_memory_region(void)
+{
+	struct memblock_region reg = {
+		.size = 0,
+	};
+
+	of_scan_flat_dt(early_init_dt_scan_usablemem, &reg);
+
+	if (reg.size)
+		memblock_cap_memory_range(reg.base, reg.size);
+}
+
+void __init arm64_memblock_init(void)
+{
+	const s64 linear_region_size = BIT(vabits_actual - 1);
+
+	/* Handle linux,usable-memory-range property */
+	fdt_enforce_memory_region();
+
+	/* Remove memory above our supported physical address size */
+	memblock_remove(1ULL << PHYS_MASK_SHIFT, ULLONG_MAX);
+
+	/*
+	 * Select a suitable value for the base of physical memory.
+	 */
+	memstart_addr = round_down(memblock_start_of_DRAM(),
+				   ARM64_MEMSTART_ALIGN);
+
+	/*
+	 * Remove the memory that we will not be able to cover with the
+	 * linear mapping. Take care not to clip the kernel which may be
+	 * high in memory.
+	 */
+	memblock_remove(max_t(u64, memstart_addr + linear_region_size,
+			__pa_symbol(_end)), ULLONG_MAX);
+	if (memstart_addr + linear_region_size < memblock_end_of_DRAM()) {
+		/* ensure that memstart_addr remains sufficiently aligned */
+		memstart_addr = round_up(memblock_end_of_DRAM() - linear_region_size,
+					 ARM64_MEMSTART_ALIGN);
+		memblock_remove(0, memstart_addr);
+	}
+
+	/*
+	 * If we are running with a 52-bit kernel VA config on a system that
+	 * does not support it, we have to place the available physical
+	 * memory in the 48-bit addressable part of the linear region, i.e.,
+	 * we have to move it upward. Since memstart_addr represents the
+	 * physical address of PAGE_OFFSET, we have to *subtract* from it.
+	 */
+	if (IS_ENABLED(CONFIG_ARM64_VA_BITS_52) && (vabits_actual != 52))
+		memstart_addr -= _PAGE_OFFSET(48) - _PAGE_OFFSET(52);
+
+	/*
+	 * Apply the memory limit if it was set. Since the kernel may be loaded
+	 * high up in memory, add back the kernel region that must be accessible
+	 * via the linear mapping.
+	 */
+	if (memory_limit != PHYS_ADDR_MAX) {
+		memblock_mem_limit_remove_map(memory_limit);
+		memblock_add(__pa_symbol(_text), (u64)(_end - _text));
+	}
+
+	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && phys_initrd_size) {
+		/*
+		 * Add back the memory we just removed if it results in the
+		 * initrd to become inaccessible via the linear mapping.
+		 * Otherwise, this is a no-op
+		 */
+		u64 base = phys_initrd_start & PAGE_MASK;
+		u64 size = PAGE_ALIGN(phys_initrd_start + phys_initrd_size) - base;
+
+		/*
+		 * We can only add back the initrd memory if we don't end up
+		 * with more memory than we can address via the linear mapping.
+		 * It is up to the bootloader to position the kernel and the
+		 * initrd reasonably close to each other (i.e., within 32 GB of
+		 * each other) so that all granule/#levels combinations can
+		 * always access both.
+		 */
+		if (WARN(base < memblock_start_of_DRAM() ||
+			 base + size > memblock_start_of_DRAM() +
+				       linear_region_size,
+			"initrd not fully accessible via the linear mapping -- please check your bootloader ...\n")) {
+			phys_initrd_size = 0;
+		} else {
+			memblock_remove(base, size); /* clear MEMBLOCK_ flags */
+			memblock_add(base, size);
+			memblock_reserve(base, size);
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+		extern u16 memstart_offset_seed;
+		u64 range = linear_region_size -
+			    (memblock_end_of_DRAM() - memblock_start_of_DRAM());
+
+		/*
+		 * If the size of the linear region exceeds, by a sufficient
+		 * margin, the size of the region that the available physical
+		 * memory spans, randomize the linear region as well.
+		 */
+		if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) {
+			range /= ARM64_MEMSTART_ALIGN;
+			memstart_addr -= ARM64_MEMSTART_ALIGN *
+					 ((range * memstart_offset_seed) >> 16);
+		}
+	}
+
+	/*
+	 * Register the kernel text, kernel data, initrd, and initial
+	 * pagetables with memblock.
+	 */
+	memblock_reserve(__pa_symbol(_text), _end - _text);
+	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && phys_initrd_size) {
+		/* the generic initrd code expects virtual addresses */
+		initrd_start = __phys_to_virt(phys_initrd_start);
+		initrd_end = initrd_start + phys_initrd_size;
+	}
+
+	early_init_fdt_scan_reserved_mem();
+
+	reserve_elfcorehdr();
+
+	if (!IS_ENABLED(CONFIG_ZONE_DMA) && !IS_ENABLED(CONFIG_ZONE_DMA32))
+		reserve_crashkernel();
+
+	high_memory = __va(memblock_end_of_DRAM() - 1) + 1;
+}
+
+void __init bootmem_init(void)
+{
+	unsigned long min, max;
+
+	min = PFN_UP(memblock_start_of_DRAM());
+	max = PFN_DOWN(memblock_end_of_DRAM());
+
+	early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT);
+
+	max_pfn = max_low_pfn = max;
+	min_low_pfn = min;
+
+	arm64_numa_init();
+
+	/*
+	 * must be done after arm64_numa_init() which calls numa_init() to
+	 * initialize node_online_map that gets used in hugetlb_cma_reserve()
+	 * while allocating required CMA size across online nodes.
+	 */
+#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_CMA)
+	arm64_hugetlb_cma_reserve();
+#endif
+
+	dma_pernuma_cma_reserve();
+
+	/*
+	 * sparse_init() tries to allocate memory from memblock, so must be
+	 * done after the fixed reservations
+	 */
+	sparse_init();
+	zone_sizes_init(min, max);
+
+	/*
+	 * Reserve the CMA area after arm64_dma_phys_limit was initialised.
+	 */
+	dma_contiguous_reserve(arm64_dma_phys_limit);
+
+	/*
+	 * request_standard_resources() depends on crashkernel's memory being
+	 * reserved, so do it here.
+	 */
+	if (IS_ENABLED(CONFIG_ZONE_DMA) || IS_ENABLED(CONFIG_ZONE_DMA32))
+		reserve_crashkernel();
+
+	memblock_dump_all();
+}
+
+#ifndef CONFIG_SPARSEMEM_VMEMMAP
+static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
+{
+	struct page *start_pg, *end_pg;
+	unsigned long pg, pgend;
+
+	/*
+	 * Convert start_pfn/end_pfn to a struct page pointer.
+	 */
+	start_pg = pfn_to_page(start_pfn - 1) + 1;
+	end_pg = pfn_to_page(end_pfn - 1) + 1;
+
+	/*
+	 * Convert to physical addresses, and round start upwards and end
+	 * downwards.
+	 */
+	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
+	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
+
+	/*
+	 * If there are free pages between these, free the section of the
+	 * memmap array.
+	 */
+	if (pg < pgend)
+		memblock_free(pg, pgend - pg);
+}
+
+/*
+ * The mem_map array can get very big. Free the unused area of the memory map.
+ */
+static void __init free_unused_memmap(void)
+{
+	unsigned long start, end, prev_end = 0;
+	int i;
+
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
+#ifdef CONFIG_SPARSEMEM
+		/*
+		 * Take care not to free memmap entries that don't exist due
+		 * to SPARSEMEM sections which aren't present.
+		 */
+		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
+#endif
+		/*
+		 * If we had a previous bank, and there is a space between the
+		 * current bank and the previous, free it.
+		 */
+		if (prev_end && prev_end < start)
+			free_memmap(prev_end, start);
+
+		/*
+		 * Align up here since the VM subsystem insists that the
+		 * memmap entries are valid from the bank end aligned to
+		 * MAX_ORDER_NR_PAGES.
+		 */
+		prev_end = ALIGN(end, MAX_ORDER_NR_PAGES);
+	}
+
+#ifdef CONFIG_SPARSEMEM
+	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
+		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
+#endif
+}
+#endif	/* !CONFIG_SPARSEMEM_VMEMMAP */
+
+/*
+ * mem_init() marks the free areas in the mem_map and tells us how much memory
+ * is free.  This is done after various parts of the system have claimed their
+ * memory after the kernel image.
+ */
+void __init mem_init(void)
+{
+	if (swiotlb_force == SWIOTLB_FORCE ||
+	    max_pfn > PFN_DOWN(arm64_dma_phys_limit))
+		swiotlb_init(1);
+	else
+		swiotlb_force = SWIOTLB_NO_FORCE;
+
+	set_max_mapnr(max_pfn - PHYS_PFN_OFFSET);
+
+#ifndef CONFIG_SPARSEMEM_VMEMMAP
+	free_unused_memmap();
+#endif
+	/* this will put all unused low memory onto the freelists */
+	memblock_free_all();
+
+	mem_init_print_info(NULL);
+
+	/*
+	 * Check boundaries twice: Some fundamental inconsistencies can be
+	 * detected at build time already.
+	 */
+#ifdef CONFIG_COMPAT
+	BUILD_BUG_ON(TASK_SIZE_32 > DEFAULT_MAP_WINDOW_64);
+#endif
+
+	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
+		extern int sysctl_overcommit_memory;
+		/*
+		 * On a machine this small we won't get anywhere without
+		 * overcommit, so turn it on by default.
+		 */
+		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
+	}
+}
+
+void free_initmem(void)
+{
+	free_reserved_area(lm_alias(__init_begin),
+			   lm_alias(__init_end),
+			   POISON_FREE_INITMEM, "unused kernel");
+	/*
+	 * Unmap the __init region but leave the VM area in place. This
+	 * prevents the region from being reused for kernel modules, which
+	 * is not supported by kallsyms.
+	 */
+	unmap_kernel_range((u64)__init_begin, (u64)(__init_end - __init_begin));
+}
+
+void dump_mem_limit(void)
+{
+	if (memory_limit != PHYS_ADDR_MAX) {
+		pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
+	} else {
+		pr_emerg("Memory Limit: none\n");
+	}
+}
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c
new file mode 100644
index 000000000..f173a01a0
--- /dev/null
+++ b/arch/arm64/mm/ioremap.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/ioremap.c
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * Hacked for ARM by Phil Blundell <philb@gnu.org>
+ * Hacked to allow all architectures to build, and various cleanups
+ * by Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <linux/memblock.h>
+
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+
+static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
+				      pgprot_t prot, void *caller)
+{
+	unsigned long last_addr;
+	unsigned long offset = phys_addr & ~PAGE_MASK;
+	int err;
+	unsigned long addr;
+	struct vm_struct *area;
+
+	/*
+	 * Page align the mapping address and size, taking account of any
+	 * offset.
+	 */
+	phys_addr &= PAGE_MASK;
+	size = PAGE_ALIGN(size + offset);
+
+	/*
+	 * Don't allow wraparound, zero size or outside PHYS_MASK.
+	 */
+	last_addr = phys_addr + size - 1;
+	if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
+		return NULL;
+
+	/*
+	 * Don't allow RAM to be mapped.
+	 */
+	if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
+		return NULL;
+
+	area = get_vm_area_caller(size, VM_IOREMAP, caller);
+	if (!area)
+		return NULL;
+	addr = (unsigned long)area->addr;
+	area->phys_addr = phys_addr;
+
+	err = ioremap_page_range(addr, addr + size, phys_addr, prot);
+	if (err) {
+		vunmap((void *)addr);
+		return NULL;
+	}
+
+	return (void __iomem *)(offset + addr);
+}
+
+void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
+{
+	return __ioremap_caller(phys_addr, size, prot,
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(__ioremap);
+
+void iounmap(volatile void __iomem *io_addr)
+{
+	unsigned long addr = (unsigned long)io_addr & PAGE_MASK;
+
+	/*
+	 * We could get an address outside vmalloc range in case
+	 * of ioremap_cache() reusing a RAM mapping.
+	 */
+	if (is_vmalloc_addr((void *)addr))
+		vunmap((void *)addr);
+}
+EXPORT_SYMBOL(iounmap);
+
+void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
+{
+	/* For normal memory we already have a cacheable mapping. */
+	if (pfn_valid(__phys_to_pfn(phys_addr)))
+		return (void __iomem *)__phys_to_virt(phys_addr);
+
+	return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_cache);
+
+/*
+ * Must be called after early_fixmap_init
+ */
+void __init early_ioremap_init(void)
+{
+	early_ioremap_setup();
+}
+
+bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
+				 unsigned long flags)
+{
+	unsigned long pfn = PHYS_PFN(offset);
+
+	return memblock_is_map_memory(pfn);
+}
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
new file mode 100644
index 000000000..b24e43d20
--- /dev/null
+++ b/arch/arm64/mm/kasan_init.c
@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This file contains kasan initialization code for ARM64.
+ *
+ * Copyright (c) 2015 Samsung Electronics Co., Ltd.
+ * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
+ */
+
+#define pr_fmt(fmt) "kasan: " fmt
+#include <linux/kasan.h>
+#include <linux/kernel.h>
+#include <linux/sched/task.h>
+#include <linux/memblock.h>
+#include <linux/start_kernel.h>
+#include <linux/mm.h>
+
+#include <asm/mmu_context.h>
+#include <asm/kernel-pgtable.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <asm/tlbflush.h>
+
+static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
+
+/*
+ * The p*d_populate functions call virt_to_phys implicitly so they can't be used
+ * directly on kernel symbols (bm_p*d). All the early functions are called too
+ * early to use lm_alias so __p*d_populate functions must be used to populate
+ * with the physical address from __pa_symbol.
+ */
+
+static phys_addr_t __init kasan_alloc_zeroed_page(int node)
+{
+	void *p = memblock_alloc_try_nid(PAGE_SIZE, PAGE_SIZE,
+					      __pa(MAX_DMA_ADDRESS),
+					      MEMBLOCK_ALLOC_KASAN, node);
+	if (!p)
+		panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d from=%llx\n",
+		      __func__, PAGE_SIZE, PAGE_SIZE, node,
+		      __pa(MAX_DMA_ADDRESS));
+
+	return __pa(p);
+}
+
+static phys_addr_t __init kasan_alloc_raw_page(int node)
+{
+	void *p = memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE,
+						__pa(MAX_DMA_ADDRESS),
+						MEMBLOCK_ALLOC_KASAN, node);
+	if (!p)
+		panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d from=%llx\n",
+		      __func__, PAGE_SIZE, PAGE_SIZE, node,
+		      __pa(MAX_DMA_ADDRESS));
+
+	return __pa(p);
+}
+
+static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node,
+				      bool early)
+{
+	if (pmd_none(READ_ONCE(*pmdp))) {
+		phys_addr_t pte_phys = early ?
+				__pa_symbol(kasan_early_shadow_pte)
+					: kasan_alloc_zeroed_page(node);
+		__pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE);
+	}
+
+	return early ? pte_offset_kimg(pmdp, addr)
+		     : pte_offset_kernel(pmdp, addr);
+}
+
+static pmd_t *__init kasan_pmd_offset(pud_t *pudp, unsigned long addr, int node,
+				      bool early)
+{
+	if (pud_none(READ_ONCE(*pudp))) {
+		phys_addr_t pmd_phys = early ?
+				__pa_symbol(kasan_early_shadow_pmd)
+					: kasan_alloc_zeroed_page(node);
+		__pud_populate(pudp, pmd_phys, PMD_TYPE_TABLE);
+	}
+
+	return early ? pmd_offset_kimg(pudp, addr) : pmd_offset(pudp, addr);
+}
+
+static pud_t *__init kasan_pud_offset(p4d_t *p4dp, unsigned long addr, int node,
+				      bool early)
+{
+	if (p4d_none(READ_ONCE(*p4dp))) {
+		phys_addr_t pud_phys = early ?
+				__pa_symbol(kasan_early_shadow_pud)
+					: kasan_alloc_zeroed_page(node);
+		__p4d_populate(p4dp, pud_phys, PMD_TYPE_TABLE);
+	}
+
+	return early ? pud_offset_kimg(p4dp, addr) : pud_offset(p4dp, addr);
+}
+
+static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
+				      unsigned long end, int node, bool early)
+{
+	unsigned long next;
+	pte_t *ptep = kasan_pte_offset(pmdp, addr, node, early);
+
+	do {
+		phys_addr_t page_phys = early ?
+				__pa_symbol(kasan_early_shadow_page)
+					: kasan_alloc_raw_page(node);
+		if (!early)
+			memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE);
+		next = addr + PAGE_SIZE;
+		set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
+	} while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
+}
+
+static void __init kasan_pmd_populate(pud_t *pudp, unsigned long addr,
+				      unsigned long end, int node, bool early)
+{
+	unsigned long next;
+	pmd_t *pmdp = kasan_pmd_offset(pudp, addr, node, early);
+
+	do {
+		next = pmd_addr_end(addr, end);
+		kasan_pte_populate(pmdp, addr, next, node, early);
+	} while (pmdp++, addr = next, addr != end && pmd_none(READ_ONCE(*pmdp)));
+}
+
+static void __init kasan_pud_populate(p4d_t *p4dp, unsigned long addr,
+				      unsigned long end, int node, bool early)
+{
+	unsigned long next;
+	pud_t *pudp = kasan_pud_offset(p4dp, addr, node, early);
+
+	do {
+		next = pud_addr_end(addr, end);
+		kasan_pmd_populate(pudp, addr, next, node, early);
+	} while (pudp++, addr = next, addr != end && pud_none(READ_ONCE(*pudp)));
+}
+
+static void __init kasan_p4d_populate(pgd_t *pgdp, unsigned long addr,
+				      unsigned long end, int node, bool early)
+{
+	unsigned long next;
+	p4d_t *p4dp = p4d_offset(pgdp, addr);
+
+	do {
+		next = p4d_addr_end(addr, end);
+		kasan_pud_populate(p4dp, addr, next, node, early);
+	} while (p4dp++, addr = next, addr != end);
+}
+
+static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
+				      int node, bool early)
+{
+	unsigned long next;
+	pgd_t *pgdp;
+
+	pgdp = pgd_offset_k(addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		kasan_p4d_populate(pgdp, addr, next, node, early);
+	} while (pgdp++, addr = next, addr != end);
+}
+
+/* The early shadow maps everything to a single page of zeroes */
+asmlinkage void __init kasan_early_init(void)
+{
+	BUILD_BUG_ON(KASAN_SHADOW_OFFSET !=
+		KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT)));
+	BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS), PGDIR_SIZE));
+	BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS_MIN), PGDIR_SIZE));
+	BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE));
+	kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE,
+			   true);
+}
+
+/* Set up full kasan mappings, ensuring that the mapped pages are zeroed */
+static void __init kasan_map_populate(unsigned long start, unsigned long end,
+				      int node)
+{
+	kasan_pgd_populate(start & PAGE_MASK, PAGE_ALIGN(end), node, false);
+}
+
+/*
+ * Copy the current shadow region into a new pgdir.
+ */
+void __init kasan_copy_shadow(pgd_t *pgdir)
+{
+	pgd_t *pgdp, *pgdp_new, *pgdp_end;
+
+	pgdp = pgd_offset_k(KASAN_SHADOW_START);
+	pgdp_end = pgd_offset_k(KASAN_SHADOW_END);
+	pgdp_new = pgd_offset_pgd(pgdir, KASAN_SHADOW_START);
+	do {
+		set_pgd(pgdp_new, READ_ONCE(*pgdp));
+	} while (pgdp++, pgdp_new++, pgdp != pgdp_end);
+}
+
+static void __init clear_pgds(unsigned long start,
+			unsigned long end)
+{
+	/*
+	 * Remove references to kasan page tables from
+	 * swapper_pg_dir. pgd_clear() can't be used
+	 * here because it's nop on 2,3-level pagetable setups
+	 */
+	for (; start < end; start += PGDIR_SIZE)
+		set_pgd(pgd_offset_k(start), __pgd(0));
+}
+
+void __init kasan_init(void)
+{
+	u64 kimg_shadow_start, kimg_shadow_end;
+	u64 mod_shadow_start, mod_shadow_end;
+	phys_addr_t pa_start, pa_end;
+	u64 i;
+
+	kimg_shadow_start = (u64)kasan_mem_to_shadow(_text) & PAGE_MASK;
+	kimg_shadow_end = PAGE_ALIGN((u64)kasan_mem_to_shadow(_end));
+
+	mod_shadow_start = (u64)kasan_mem_to_shadow((void *)MODULES_VADDR);
+	mod_shadow_end = (u64)kasan_mem_to_shadow((void *)MODULES_END);
+
+	/*
+	 * We are going to perform proper setup of shadow memory.
+	 * At first we should unmap early shadow (clear_pgds() call below).
+	 * However, instrumented code couldn't execute without shadow memory.
+	 * tmp_pg_dir used to keep early shadow mapped until full shadow
+	 * setup will be finished.
+	 */
+	memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
+	dsb(ishst);
+	cpu_replace_ttbr1(lm_alias(tmp_pg_dir));
+
+	clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
+
+	kasan_map_populate(kimg_shadow_start, kimg_shadow_end,
+			   early_pfn_to_nid(virt_to_pfn(lm_alias(_text))));
+
+	kasan_populate_early_shadow(kasan_mem_to_shadow((void *)PAGE_END),
+				   (void *)mod_shadow_start);
+	kasan_populate_early_shadow((void *)kimg_shadow_end,
+				   (void *)KASAN_SHADOW_END);
+
+	if (kimg_shadow_start > mod_shadow_end)
+		kasan_populate_early_shadow((void *)mod_shadow_end,
+					    (void *)kimg_shadow_start);
+
+	for_each_mem_range(i, &pa_start, &pa_end) {
+		void *start = (void *)__phys_to_virt(pa_start);
+		void *end = (void *)__phys_to_virt(pa_end);
+
+		if (start >= end)
+			break;
+
+		kasan_map_populate((unsigned long)kasan_mem_to_shadow(start),
+				   (unsigned long)kasan_mem_to_shadow(end),
+				   early_pfn_to_nid(virt_to_pfn(start)));
+	}
+
+	/*
+	 * KAsan may reuse the contents of kasan_early_shadow_pte directly,
+	 * so we should make sure that it maps the zero page read-only.
+	 */
+	for (i = 0; i < PTRS_PER_PTE; i++)
+		set_pte(&kasan_early_shadow_pte[i],
+			pfn_pte(sym_to_pfn(kasan_early_shadow_page),
+				PAGE_KERNEL_RO));
+
+	memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
+	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
+
+	/* At this point kasan is fully initialized. Enable error messages */
+	init_task.kasan_depth = 0;
+	pr_info("KernelAddressSanitizer initialized\n");
+}
diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
new file mode 100644
index 000000000..3028bacbc
--- /dev/null
+++ b/arch/arm64/mm/mmap.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/mmap.c
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/elf.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/export.h>
+#include <linux/shm.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
+#include <linux/io.h>
+#include <linux/personality.h>
+#include <linux/random.h>
+
+#include <asm/cputype.h>
+
+/*
+ * You really shouldn't be using read() or write() on /dev/mem.  This might go
+ * away in the future.
+ */
+int valid_phys_addr_range(phys_addr_t addr, size_t size)
+{
+	/*
+	 * Check whether addr is covered by a memory region without the
+	 * MEMBLOCK_NOMAP attribute, and whether that region covers the
+	 * entire range. In theory, this could lead to false negatives
+	 * if the range is covered by distinct but adjacent memory regions
+	 * that only differ in other attributes. However, few of such
+	 * attributes have been defined, and it is debatable whether it
+	 * follows that /dev/mem read() calls should be able traverse
+	 * such boundaries.
+	 */
+	return memblock_is_region_memory(addr, size) &&
+	       memblock_is_map_memory(addr);
+}
+
+/*
+ * Do not allow /dev/mem mappings beyond the supported physical range.
+ */
+int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
+{
+	return !(((pfn << PAGE_SHIFT) + size) & ~PHYS_MASK);
+}
+
+#ifdef CONFIG_STRICT_DEVMEM
+
+#include <linux/ioport.h>
+
+/*
+ * devmem_is_allowed() checks to see if /dev/mem access to a certain address
+ * is valid. The argument is a physical page number.  We mimic x86 here by
+ * disallowing access to system RAM as well as device-exclusive MMIO regions.
+ * This effectively disable read()/write() on /dev/mem.
+ */
+int devmem_is_allowed(unsigned long pfn)
+{
+	if (iomem_is_exclusive(pfn << PAGE_SHIFT))
+		return 0;
+	if (!page_is_ram(pfn))
+		return 1;
+	return 0;
+}
+
+#endif
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
new file mode 100644
index 000000000..78f9fb638
--- /dev/null
+++ b/arch/arm64/mm/mmu.c
@@ -0,0 +1,1595 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/mmu.c
+ *
+ * Copyright (C) 1995-2005 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/cache.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/memblock.h>
+#include <linux/memory.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+
+#include <asm/barrier.h>
+#include <asm/cputype.h>
+#include <asm/fixmap.h>
+#include <asm/kasan.h>
+#include <asm/kernel-pgtable.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <linux/sizes.h>
+#include <asm/tlb.h>
+#include <asm/mmu_context.h>
+#include <asm/ptdump.h>
+#include <asm/tlbflush.h>
+#include <asm/pgalloc.h>
+
+#define NO_BLOCK_MAPPINGS	BIT(0)
+#define NO_CONT_MAPPINGS	BIT(1)
+
+u64 idmap_t0sz = TCR_T0SZ(VA_BITS_MIN);
+u64 idmap_ptrs_per_pgd = PTRS_PER_PGD;
+
+u64 __section(".mmuoff.data.write") vabits_actual;
+EXPORT_SYMBOL(vabits_actual);
+
+u64 kimage_voffset __ro_after_init;
+EXPORT_SYMBOL(kimage_voffset);
+
+/*
+ * Empty_zero_page is a special page that is used for zero-initialized data
+ * and COW.
+ */
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
+EXPORT_SYMBOL(empty_zero_page);
+
+static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
+static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused;
+static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused;
+
+static DEFINE_SPINLOCK(swapper_pgdir_lock);
+static DEFINE_MUTEX(fixmap_lock);
+
+void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd)
+{
+	pgd_t *fixmap_pgdp;
+
+	spin_lock(&swapper_pgdir_lock);
+	fixmap_pgdp = pgd_set_fixmap(__pa_symbol(pgdp));
+	WRITE_ONCE(*fixmap_pgdp, pgd);
+	/*
+	 * We need dsb(ishst) here to ensure the page-table-walker sees
+	 * our new entry before set_p?d() returns. The fixmap's
+	 * flush_tlb_kernel_range() via clear_fixmap() does this for us.
+	 */
+	pgd_clear_fixmap();
+	spin_unlock(&swapper_pgdir_lock);
+}
+
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+			      unsigned long size, pgprot_t vma_prot)
+{
+	if (!pfn_valid(pfn))
+		return pgprot_noncached(vma_prot);
+	else if (file->f_flags & O_SYNC)
+		return pgprot_writecombine(vma_prot);
+	return vma_prot;
+}
+EXPORT_SYMBOL(phys_mem_access_prot);
+
+static phys_addr_t __init early_pgtable_alloc(int shift)
+{
+	phys_addr_t phys;
+	void *ptr;
+
+	phys = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+	if (!phys)
+		panic("Failed to allocate page table page\n");
+
+	/*
+	 * The FIX_{PGD,PUD,PMD} slots may be in active use, but the FIX_PTE
+	 * slot will be free, so we can (ab)use the FIX_PTE slot to initialise
+	 * any level of table.
+	 */
+	ptr = pte_set_fixmap(phys);
+
+	memset(ptr, 0, PAGE_SIZE);
+
+	/*
+	 * Implicit barriers also ensure the zeroed page is visible to the page
+	 * table walker
+	 */
+	pte_clear_fixmap();
+
+	return phys;
+}
+
+static bool pgattr_change_is_safe(u64 old, u64 new)
+{
+	/*
+	 * The following mapping attributes may be updated in live
+	 * kernel mappings without the need for break-before-make.
+	 */
+	pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE | PTE_NG;
+
+	/* creating or taking down mappings is always safe */
+	if (old == 0 || new == 0)
+		return true;
+
+	/* live contiguous mappings may not be manipulated at all */
+	if ((old | new) & PTE_CONT)
+		return false;
+
+	/* Transitioning from Non-Global to Global is unsafe */
+	if (old & ~new & PTE_NG)
+		return false;
+
+	/*
+	 * Changing the memory type between Normal and Normal-Tagged is safe
+	 * since Tagged is considered a permission attribute from the
+	 * mismatched attribute aliases perspective.
+	 */
+	if (((old & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL) ||
+	     (old & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL_TAGGED)) &&
+	    ((new & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL) ||
+	     (new & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL_TAGGED)))
+		mask |= PTE_ATTRINDX_MASK;
+
+	return ((old ^ new) & ~mask) == 0;
+}
+
+static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end,
+		     phys_addr_t phys, pgprot_t prot)
+{
+	pte_t *ptep;
+
+	ptep = pte_set_fixmap_offset(pmdp, addr);
+	do {
+		pte_t old_pte = READ_ONCE(*ptep);
+
+		set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot));
+
+		/*
+		 * After the PTE entry has been populated once, we
+		 * only allow updates to the permission attributes.
+		 */
+		BUG_ON(!pgattr_change_is_safe(pte_val(old_pte),
+					      READ_ONCE(pte_val(*ptep))));
+
+		phys += PAGE_SIZE;
+	} while (ptep++, addr += PAGE_SIZE, addr != end);
+
+	pte_clear_fixmap();
+}
+
+static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr,
+				unsigned long end, phys_addr_t phys,
+				pgprot_t prot,
+				phys_addr_t (*pgtable_alloc)(int),
+				int flags)
+{
+	unsigned long next;
+	pmd_t pmd = READ_ONCE(*pmdp);
+
+	BUG_ON(pmd_sect(pmd));
+	if (pmd_none(pmd)) {
+		phys_addr_t pte_phys;
+		BUG_ON(!pgtable_alloc);
+		pte_phys = pgtable_alloc(PAGE_SHIFT);
+		__pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE);
+		pmd = READ_ONCE(*pmdp);
+	}
+	BUG_ON(pmd_bad(pmd));
+
+	do {
+		pgprot_t __prot = prot;
+
+		next = pte_cont_addr_end(addr, end);
+
+		/* use a contiguous mapping if the range is suitably aligned */
+		if ((((addr | next | phys) & ~CONT_PTE_MASK) == 0) &&
+		    (flags & NO_CONT_MAPPINGS) == 0)
+			__prot = __pgprot(pgprot_val(prot) | PTE_CONT);
+
+		init_pte(pmdp, addr, next, phys, __prot);
+
+		phys += next - addr;
+	} while (addr = next, addr != end);
+}
+
+static void init_pmd(pud_t *pudp, unsigned long addr, unsigned long end,
+		     phys_addr_t phys, pgprot_t prot,
+		     phys_addr_t (*pgtable_alloc)(int), int flags)
+{
+	unsigned long next;
+	pmd_t *pmdp;
+
+	pmdp = pmd_set_fixmap_offset(pudp, addr);
+	do {
+		pmd_t old_pmd = READ_ONCE(*pmdp);
+
+		next = pmd_addr_end(addr, end);
+
+		/* try section mapping first */
+		if (((addr | next | phys) & ~SECTION_MASK) == 0 &&
+		    (flags & NO_BLOCK_MAPPINGS) == 0) {
+			pmd_set_huge(pmdp, phys, prot);
+
+			/*
+			 * After the PMD entry has been populated once, we
+			 * only allow updates to the permission attributes.
+			 */
+			BUG_ON(!pgattr_change_is_safe(pmd_val(old_pmd),
+						      READ_ONCE(pmd_val(*pmdp))));
+		} else {
+			alloc_init_cont_pte(pmdp, addr, next, phys, prot,
+					    pgtable_alloc, flags);
+
+			BUG_ON(pmd_val(old_pmd) != 0 &&
+			       pmd_val(old_pmd) != READ_ONCE(pmd_val(*pmdp)));
+		}
+		phys += next - addr;
+	} while (pmdp++, addr = next, addr != end);
+
+	pmd_clear_fixmap();
+}
+
+static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
+				unsigned long end, phys_addr_t phys,
+				pgprot_t prot,
+				phys_addr_t (*pgtable_alloc)(int), int flags)
+{
+	unsigned long next;
+	pud_t pud = READ_ONCE(*pudp);
+
+	/*
+	 * Check for initial section mappings in the pgd/pud.
+	 */
+	BUG_ON(pud_sect(pud));
+	if (pud_none(pud)) {
+		phys_addr_t pmd_phys;
+		BUG_ON(!pgtable_alloc);
+		pmd_phys = pgtable_alloc(PMD_SHIFT);
+		__pud_populate(pudp, pmd_phys, PUD_TYPE_TABLE);
+		pud = READ_ONCE(*pudp);
+	}
+	BUG_ON(pud_bad(pud));
+
+	do {
+		pgprot_t __prot = prot;
+
+		next = pmd_cont_addr_end(addr, end);
+
+		/* use a contiguous mapping if the range is suitably aligned */
+		if ((((addr | next | phys) & ~CONT_PMD_MASK) == 0) &&
+		    (flags & NO_CONT_MAPPINGS) == 0)
+			__prot = __pgprot(pgprot_val(prot) | PTE_CONT);
+
+		init_pmd(pudp, addr, next, phys, __prot, pgtable_alloc, flags);
+
+		phys += next - addr;
+	} while (addr = next, addr != end);
+}
+
+static inline bool use_1G_block(unsigned long addr, unsigned long next,
+			unsigned long phys)
+{
+	if (PAGE_SHIFT != 12)
+		return false;
+
+	if (((addr | next | phys) & ~PUD_MASK) != 0)
+		return false;
+
+	return true;
+}
+
+static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
+			   phys_addr_t phys, pgprot_t prot,
+			   phys_addr_t (*pgtable_alloc)(int),
+			   int flags)
+{
+	unsigned long next;
+	pud_t *pudp;
+	p4d_t *p4dp = p4d_offset(pgdp, addr);
+	p4d_t p4d = READ_ONCE(*p4dp);
+
+	if (p4d_none(p4d)) {
+		phys_addr_t pud_phys;
+		BUG_ON(!pgtable_alloc);
+		pud_phys = pgtable_alloc(PUD_SHIFT);
+		__p4d_populate(p4dp, pud_phys, PUD_TYPE_TABLE);
+		p4d = READ_ONCE(*p4dp);
+	}
+	BUG_ON(p4d_bad(p4d));
+
+	/*
+	 * No need for locking during early boot. And it doesn't work as
+	 * expected with KASLR enabled.
+	 */
+	if (system_state != SYSTEM_BOOTING)
+		mutex_lock(&fixmap_lock);
+	pudp = pud_set_fixmap_offset(p4dp, addr);
+	do {
+		pud_t old_pud = READ_ONCE(*pudp);
+
+		next = pud_addr_end(addr, end);
+
+		/*
+		 * For 4K granule only, attempt to put down a 1GB block
+		 */
+		if (use_1G_block(addr, next, phys) &&
+		    (flags & NO_BLOCK_MAPPINGS) == 0) {
+			pud_set_huge(pudp, phys, prot);
+
+			/*
+			 * After the PUD entry has been populated once, we
+			 * only allow updates to the permission attributes.
+			 */
+			BUG_ON(!pgattr_change_is_safe(pud_val(old_pud),
+						      READ_ONCE(pud_val(*pudp))));
+		} else {
+			alloc_init_cont_pmd(pudp, addr, next, phys, prot,
+					    pgtable_alloc, flags);
+
+			BUG_ON(pud_val(old_pud) != 0 &&
+			       pud_val(old_pud) != READ_ONCE(pud_val(*pudp)));
+		}
+		phys += next - addr;
+	} while (pudp++, addr = next, addr != end);
+
+	pud_clear_fixmap();
+	if (system_state != SYSTEM_BOOTING)
+		mutex_unlock(&fixmap_lock);
+}
+
+static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
+				 unsigned long virt, phys_addr_t size,
+				 pgprot_t prot,
+				 phys_addr_t (*pgtable_alloc)(int),
+				 int flags)
+{
+	unsigned long addr, end, next;
+	pgd_t *pgdp = pgd_offset_pgd(pgdir, virt);
+
+	/*
+	 * If the virtual and physical address don't have the same offset
+	 * within a page, we cannot map the region as the caller expects.
+	 */
+	if (WARN_ON((phys ^ virt) & ~PAGE_MASK))
+		return;
+
+	phys &= PAGE_MASK;
+	addr = virt & PAGE_MASK;
+	end = PAGE_ALIGN(virt + size);
+
+	do {
+		next = pgd_addr_end(addr, end);
+		alloc_init_pud(pgdp, addr, next, phys, prot, pgtable_alloc,
+			       flags);
+		phys += next - addr;
+	} while (pgdp++, addr = next, addr != end);
+}
+
+static phys_addr_t __pgd_pgtable_alloc(int shift)
+{
+	void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL);
+	BUG_ON(!ptr);
+
+	/* Ensure the zeroed page is visible to the page table walker */
+	dsb(ishst);
+	return __pa(ptr);
+}
+
+static phys_addr_t pgd_pgtable_alloc(int shift)
+{
+	phys_addr_t pa = __pgd_pgtable_alloc(shift);
+
+	/*
+	 * Call proper page table ctor in case later we need to
+	 * call core mm functions like apply_to_page_range() on
+	 * this pre-allocated page table.
+	 *
+	 * We don't select ARCH_ENABLE_SPLIT_PMD_PTLOCK if pmd is
+	 * folded, and if so pgtable_pmd_page_ctor() becomes nop.
+	 */
+	if (shift == PAGE_SHIFT)
+		BUG_ON(!pgtable_pte_page_ctor(phys_to_page(pa)));
+	else if (shift == PMD_SHIFT)
+		BUG_ON(!pgtable_pmd_page_ctor(phys_to_page(pa)));
+
+	return pa;
+}
+
+/*
+ * This function can only be used to modify existing table entries,
+ * without allocating new levels of table. Note that this permits the
+ * creation of new section or page entries.
+ */
+static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt,
+				  phys_addr_t size, pgprot_t prot)
+{
+	if (virt < PAGE_OFFSET) {
+		pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n",
+			&phys, virt);
+		return;
+	}
+	__create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
+			     NO_CONT_MAPPINGS);
+}
+
+void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
+			       unsigned long virt, phys_addr_t size,
+			       pgprot_t prot, bool page_mappings_only)
+{
+	int flags = 0;
+
+	BUG_ON(mm == &init_mm);
+
+	if (page_mappings_only)
+		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
+
+	__create_pgd_mapping(mm->pgd, phys, virt, size, prot,
+			     pgd_pgtable_alloc, flags);
+}
+
+static void update_mapping_prot(phys_addr_t phys, unsigned long virt,
+				phys_addr_t size, pgprot_t prot)
+{
+	if (virt < PAGE_OFFSET) {
+		pr_warn("BUG: not updating mapping for %pa at 0x%016lx - outside kernel range\n",
+			&phys, virt);
+		return;
+	}
+
+	__create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
+			     NO_CONT_MAPPINGS);
+
+	/* flush the TLBs after updating live kernel mappings */
+	flush_tlb_kernel_range(virt, virt + size);
+}
+
+static void __init __map_memblock(pgd_t *pgdp, phys_addr_t start,
+				  phys_addr_t end, pgprot_t prot, int flags)
+{
+	__create_pgd_mapping(pgdp, start, __phys_to_virt(start), end - start,
+			     prot, early_pgtable_alloc, flags);
+}
+
+void __init mark_linear_text_alias_ro(void)
+{
+	/*
+	 * Remove the write permissions from the linear alias of .text/.rodata
+	 */
+	update_mapping_prot(__pa_symbol(_text), (unsigned long)lm_alias(_text),
+			    (unsigned long)__init_begin - (unsigned long)_text,
+			    PAGE_KERNEL_RO);
+}
+
+static bool crash_mem_map __initdata;
+
+static int __init enable_crash_mem_map(char *arg)
+{
+	/*
+	 * Proper parameter parsing is done by reserve_crashkernel(). We only
+	 * need to know if the linear map has to avoid block mappings so that
+	 * the crashkernel reservations can be unmapped later.
+	 */
+	crash_mem_map = true;
+
+	return 0;
+}
+early_param("crashkernel", enable_crash_mem_map);
+
+static void __init map_mem(pgd_t *pgdp)
+{
+	phys_addr_t kernel_start = __pa_symbol(_text);
+	phys_addr_t kernel_end = __pa_symbol(__init_begin);
+	phys_addr_t start, end;
+	int flags = 0;
+	u64 i;
+
+	if (rodata_full || debug_pagealloc_enabled())
+		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
+
+	/*
+	 * Take care not to create a writable alias for the
+	 * read-only text and rodata sections of the kernel image.
+	 * So temporarily mark them as NOMAP to skip mappings in
+	 * the following for-loop
+	 */
+	memblock_mark_nomap(kernel_start, kernel_end - kernel_start);
+
+#ifdef CONFIG_KEXEC_CORE
+	if (crash_mem_map) {
+		if (IS_ENABLED(CONFIG_ZONE_DMA) ||
+		    IS_ENABLED(CONFIG_ZONE_DMA32))
+			flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
+		else if (crashk_res.end)
+			memblock_mark_nomap(crashk_res.start,
+					    resource_size(&crashk_res));
+	}
+#endif
+
+	/* map all the memory banks */
+	for_each_mem_range(i, &start, &end) {
+		if (start >= end)
+			break;
+		/*
+		 * The linear map must allow allocation tags reading/writing
+		 * if MTE is present. Otherwise, it has the same attributes as
+		 * PAGE_KERNEL.
+		 */
+		__map_memblock(pgdp, start, end, pgprot_tagged(PAGE_KERNEL),
+			       flags);
+	}
+
+	/*
+	 * Map the linear alias of the [_text, __init_begin) interval
+	 * as non-executable now, and remove the write permission in
+	 * mark_linear_text_alias_ro() below (which will be called after
+	 * alternative patching has completed). This makes the contents
+	 * of the region accessible to subsystems such as hibernate,
+	 * but protects it from inadvertent modification or execution.
+	 * Note that contiguous mappings cannot be remapped in this way,
+	 * so we should avoid them here.
+	 */
+	__map_memblock(pgdp, kernel_start, kernel_end,
+		       PAGE_KERNEL, NO_CONT_MAPPINGS);
+	memblock_clear_nomap(kernel_start, kernel_end - kernel_start);
+
+	/*
+	 * Use page-level mappings here so that we can shrink the region
+	 * in page granularity and put back unused memory to buddy system
+	 * through /sys/kernel/kexec_crash_size interface.
+	 */
+#ifdef CONFIG_KEXEC_CORE
+	if (crash_mem_map &&
+	    !IS_ENABLED(CONFIG_ZONE_DMA) && !IS_ENABLED(CONFIG_ZONE_DMA32)) {
+		if (crashk_res.end) {
+			__map_memblock(pgdp, crashk_res.start,
+				       crashk_res.end + 1,
+				       PAGE_KERNEL,
+				       NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS);
+			memblock_clear_nomap(crashk_res.start,
+					     resource_size(&crashk_res));
+		}
+	}
+#endif
+}
+
+void mark_rodata_ro(void)
+{
+	unsigned long section_size;
+
+	/*
+	 * mark .rodata as read only. Use __init_begin rather than __end_rodata
+	 * to cover NOTES and EXCEPTION_TABLE.
+	 */
+	section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata;
+	update_mapping_prot(__pa_symbol(__start_rodata), (unsigned long)__start_rodata,
+			    section_size, PAGE_KERNEL_RO);
+
+	debug_checkwx();
+}
+
+static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
+				      pgprot_t prot, struct vm_struct *vma,
+				      int flags, unsigned long vm_flags)
+{
+	phys_addr_t pa_start = __pa_symbol(va_start);
+	unsigned long size = va_end - va_start;
+
+	BUG_ON(!PAGE_ALIGNED(pa_start));
+	BUG_ON(!PAGE_ALIGNED(size));
+
+	__create_pgd_mapping(pgdp, pa_start, (unsigned long)va_start, size, prot,
+			     early_pgtable_alloc, flags);
+
+	if (!(vm_flags & VM_NO_GUARD))
+		size += PAGE_SIZE;
+
+	vma->addr	= va_start;
+	vma->phys_addr	= pa_start;
+	vma->size	= size;
+	vma->flags	= VM_MAP | vm_flags;
+	vma->caller	= __builtin_return_address(0);
+
+	vm_area_add_early(vma);
+}
+
+static int __init parse_rodata(char *arg)
+{
+	int ret = strtobool(arg, &rodata_enabled);
+	if (!ret) {
+		rodata_full = false;
+		return 0;
+	}
+
+	/* permit 'full' in addition to boolean options */
+	if (strcmp(arg, "full"))
+		return -EINVAL;
+
+	rodata_enabled = true;
+	rodata_full = true;
+	return 0;
+}
+early_param("rodata", parse_rodata);
+
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+static int __init map_entry_trampoline(void)
+{
+	int i;
+
+	pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
+	phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start);
+
+	/* The trampoline is always mapped and can therefore be global */
+	pgprot_val(prot) &= ~PTE_NG;
+
+	/* Map only the text into the trampoline page table */
+	memset(tramp_pg_dir, 0, PGD_SIZE);
+	__create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS,
+			     entry_tramp_text_size(), prot,
+			     __pgd_pgtable_alloc, NO_BLOCK_MAPPINGS);
+
+	/* Map both the text and data into the kernel page table */
+	for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++)
+		__set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i,
+			     pa_start + i * PAGE_SIZE, prot);
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+		extern char __entry_tramp_data_start[];
+
+		__set_fixmap(FIX_ENTRY_TRAMP_DATA,
+			     __pa_symbol(__entry_tramp_data_start),
+			     PAGE_KERNEL_RO);
+	}
+
+	return 0;
+}
+core_initcall(map_entry_trampoline);
+#endif
+
+/*
+ * Open coded check for BTI, only for use to determine configuration
+ * for early mappings for before the cpufeature code has run.
+ */
+static bool arm64_early_this_cpu_has_bti(void)
+{
+	u64 pfr1;
+
+	if (!IS_ENABLED(CONFIG_ARM64_BTI_KERNEL))
+		return false;
+
+	pfr1 = read_sysreg_s(SYS_ID_AA64PFR1_EL1);
+	return cpuid_feature_extract_unsigned_field(pfr1,
+						    ID_AA64PFR1_BT_SHIFT);
+}
+
+/*
+ * Create fine-grained mappings for the kernel.
+ */
+static void __init map_kernel(pgd_t *pgdp)
+{
+	static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_inittext,
+				vmlinux_initdata, vmlinux_data;
+
+	/*
+	 * External debuggers may need to write directly to the text
+	 * mapping to install SW breakpoints. Allow this (only) when
+	 * explicitly requested with rodata=off.
+	 */
+	pgprot_t text_prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
+
+	/*
+	 * If we have a CPU that supports BTI and a kernel built for
+	 * BTI then mark the kernel executable text as guarded pages
+	 * now so we don't have to rewrite the page tables later.
+	 */
+	if (arm64_early_this_cpu_has_bti())
+		text_prot = __pgprot_modify(text_prot, PTE_GP, PTE_GP);
+
+	/*
+	 * Only rodata will be remapped with different permissions later on,
+	 * all other segments are allowed to use contiguous mappings.
+	 */
+	map_kernel_segment(pgdp, _text, _etext, text_prot, &vmlinux_text, 0,
+			   VM_NO_GUARD);
+	map_kernel_segment(pgdp, __start_rodata, __inittext_begin, PAGE_KERNEL,
+			   &vmlinux_rodata, NO_CONT_MAPPINGS, VM_NO_GUARD);
+	map_kernel_segment(pgdp, __inittext_begin, __inittext_end, text_prot,
+			   &vmlinux_inittext, 0, VM_NO_GUARD);
+	map_kernel_segment(pgdp, __initdata_begin, __initdata_end, PAGE_KERNEL,
+			   &vmlinux_initdata, 0, VM_NO_GUARD);
+	map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0);
+
+	if (!READ_ONCE(pgd_val(*pgd_offset_pgd(pgdp, FIXADDR_START)))) {
+		/*
+		 * The fixmap falls in a separate pgd to the kernel, and doesn't
+		 * live in the carveout for the swapper_pg_dir. We can simply
+		 * re-use the existing dir for the fixmap.
+		 */
+		set_pgd(pgd_offset_pgd(pgdp, FIXADDR_START),
+			READ_ONCE(*pgd_offset_k(FIXADDR_START)));
+	} else if (CONFIG_PGTABLE_LEVELS > 3) {
+		pgd_t *bm_pgdp;
+		p4d_t *bm_p4dp;
+		pud_t *bm_pudp;
+		/*
+		 * The fixmap shares its top level pgd entry with the kernel
+		 * mapping. This can really only occur when we are running
+		 * with 16k/4 levels, so we can simply reuse the pud level
+		 * entry instead.
+		 */
+		BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
+		bm_pgdp = pgd_offset_pgd(pgdp, FIXADDR_START);
+		bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_START);
+		bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_START);
+		pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd));
+		pud_clear_fixmap();
+	} else {
+		BUG();
+	}
+
+	kasan_copy_shadow(pgdp);
+}
+
+void __init paging_init(void)
+{
+	pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir));
+
+	map_kernel(pgdp);
+	map_mem(pgdp);
+
+	pgd_clear_fixmap();
+
+	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
+	init_mm.pgd = swapper_pg_dir;
+
+	memblock_free(__pa_symbol(init_pg_dir),
+		      __pa_symbol(init_pg_end) - __pa_symbol(init_pg_dir));
+
+	memblock_allow_resize();
+}
+
+/*
+ * Check whether a kernel address is valid (derived from arch/x86/).
+ */
+int kern_addr_valid(unsigned long addr)
+{
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp, pud;
+	pmd_t *pmdp, pmd;
+	pte_t *ptep, pte;
+
+	addr = arch_kasan_reset_tag(addr);
+	if ((((long)addr) >> VA_BITS) != -1UL)
+		return 0;
+
+	pgdp = pgd_offset_k(addr);
+	if (pgd_none(READ_ONCE(*pgdp)))
+		return 0;
+
+	p4dp = p4d_offset(pgdp, addr);
+	if (p4d_none(READ_ONCE(*p4dp)))
+		return 0;
+
+	pudp = pud_offset(p4dp, addr);
+	pud = READ_ONCE(*pudp);
+	if (pud_none(pud))
+		return 0;
+
+	if (pud_sect(pud))
+		return pfn_valid(pud_pfn(pud));
+
+	pmdp = pmd_offset(pudp, addr);
+	pmd = READ_ONCE(*pmdp);
+	if (pmd_none(pmd))
+		return 0;
+
+	if (pmd_sect(pmd))
+		return pfn_valid(pmd_pfn(pmd));
+
+	ptep = pte_offset_kernel(pmdp, addr);
+	pte = READ_ONCE(*ptep);
+	if (pte_none(pte))
+		return 0;
+
+	return pfn_valid(pte_pfn(pte));
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static void free_hotplug_page_range(struct page *page, size_t size,
+				    struct vmem_altmap *altmap)
+{
+	if (altmap) {
+		vmem_altmap_free(altmap, size >> PAGE_SHIFT);
+	} else {
+		WARN_ON(PageReserved(page));
+		free_pages((unsigned long)page_address(page), get_order(size));
+	}
+}
+
+static void free_hotplug_pgtable_page(struct page *page)
+{
+	free_hotplug_page_range(page, PAGE_SIZE, NULL);
+}
+
+static bool pgtable_range_aligned(unsigned long start, unsigned long end,
+				  unsigned long floor, unsigned long ceiling,
+				  unsigned long mask)
+{
+	start &= mask;
+	if (start < floor)
+		return false;
+
+	if (ceiling) {
+		ceiling &= mask;
+		if (!ceiling)
+			return false;
+	}
+
+	if (end - 1 > ceiling - 1)
+		return false;
+	return true;
+}
+
+static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr,
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
+{
+	pte_t *ptep, pte;
+
+	do {
+		ptep = pte_offset_kernel(pmdp, addr);
+		pte = READ_ONCE(*ptep);
+		if (pte_none(pte))
+			continue;
+
+		WARN_ON(!pte_present(pte));
+		pte_clear(&init_mm, addr, ptep);
+		flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+		if (free_mapped)
+			free_hotplug_page_range(pte_page(pte),
+						PAGE_SIZE, altmap);
+	} while (addr += PAGE_SIZE, addr < end);
+}
+
+static void unmap_hotplug_pmd_range(pud_t *pudp, unsigned long addr,
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
+{
+	unsigned long next;
+	pmd_t *pmdp, pmd;
+
+	do {
+		next = pmd_addr_end(addr, end);
+		pmdp = pmd_offset(pudp, addr);
+		pmd = READ_ONCE(*pmdp);
+		if (pmd_none(pmd))
+			continue;
+
+		WARN_ON(!pmd_present(pmd));
+		if (pmd_sect(pmd)) {
+			pmd_clear(pmdp);
+
+			/*
+			 * One TLBI should be sufficient here as the PMD_SIZE
+			 * range is mapped with a single block entry.
+			 */
+			flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+			if (free_mapped)
+				free_hotplug_page_range(pmd_page(pmd),
+							PMD_SIZE, altmap);
+			continue;
+		}
+		WARN_ON(!pmd_table(pmd));
+		unmap_hotplug_pte_range(pmdp, addr, next, free_mapped, altmap);
+	} while (addr = next, addr < end);
+}
+
+static void unmap_hotplug_pud_range(p4d_t *p4dp, unsigned long addr,
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
+{
+	unsigned long next;
+	pud_t *pudp, pud;
+
+	do {
+		next = pud_addr_end(addr, end);
+		pudp = pud_offset(p4dp, addr);
+		pud = READ_ONCE(*pudp);
+		if (pud_none(pud))
+			continue;
+
+		WARN_ON(!pud_present(pud));
+		if (pud_sect(pud)) {
+			pud_clear(pudp);
+
+			/*
+			 * One TLBI should be sufficient here as the PUD_SIZE
+			 * range is mapped with a single block entry.
+			 */
+			flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+			if (free_mapped)
+				free_hotplug_page_range(pud_page(pud),
+							PUD_SIZE, altmap);
+			continue;
+		}
+		WARN_ON(!pud_table(pud));
+		unmap_hotplug_pmd_range(pudp, addr, next, free_mapped, altmap);
+	} while (addr = next, addr < end);
+}
+
+static void unmap_hotplug_p4d_range(pgd_t *pgdp, unsigned long addr,
+				    unsigned long end, bool free_mapped,
+				    struct vmem_altmap *altmap)
+{
+	unsigned long next;
+	p4d_t *p4dp, p4d;
+
+	do {
+		next = p4d_addr_end(addr, end);
+		p4dp = p4d_offset(pgdp, addr);
+		p4d = READ_ONCE(*p4dp);
+		if (p4d_none(p4d))
+			continue;
+
+		WARN_ON(!p4d_present(p4d));
+		unmap_hotplug_pud_range(p4dp, addr, next, free_mapped, altmap);
+	} while (addr = next, addr < end);
+}
+
+static void unmap_hotplug_range(unsigned long addr, unsigned long end,
+				bool free_mapped, struct vmem_altmap *altmap)
+{
+	unsigned long next;
+	pgd_t *pgdp, pgd;
+
+	/*
+	 * altmap can only be used as vmemmap mapping backing memory.
+	 * In case the backing memory itself is not being freed, then
+	 * altmap is irrelevant. Warn about this inconsistency when
+	 * encountered.
+	 */
+	WARN_ON(!free_mapped && altmap);
+
+	do {
+		next = pgd_addr_end(addr, end);
+		pgdp = pgd_offset_k(addr);
+		pgd = READ_ONCE(*pgdp);
+		if (pgd_none(pgd))
+			continue;
+
+		WARN_ON(!pgd_present(pgd));
+		unmap_hotplug_p4d_range(pgdp, addr, next, free_mapped, altmap);
+	} while (addr = next, addr < end);
+}
+
+static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr,
+				 unsigned long end, unsigned long floor,
+				 unsigned long ceiling)
+{
+	pte_t *ptep, pte;
+	unsigned long i, start = addr;
+
+	do {
+		ptep = pte_offset_kernel(pmdp, addr);
+		pte = READ_ONCE(*ptep);
+
+		/*
+		 * This is just a sanity check here which verifies that
+		 * pte clearing has been done by earlier unmap loops.
+		 */
+		WARN_ON(!pte_none(pte));
+	} while (addr += PAGE_SIZE, addr < end);
+
+	if (!pgtable_range_aligned(start, end, floor, ceiling, PMD_MASK))
+		return;
+
+	/*
+	 * Check whether we can free the pte page if the rest of the
+	 * entries are empty. Overlap with other regions have been
+	 * handled by the floor/ceiling check.
+	 */
+	ptep = pte_offset_kernel(pmdp, 0UL);
+	for (i = 0; i < PTRS_PER_PTE; i++) {
+		if (!pte_none(READ_ONCE(ptep[i])))
+			return;
+	}
+
+	pmd_clear(pmdp);
+	__flush_tlb_kernel_pgtable(start);
+	free_hotplug_pgtable_page(virt_to_page(ptep));
+}
+
+static void free_empty_pmd_table(pud_t *pudp, unsigned long addr,
+				 unsigned long end, unsigned long floor,
+				 unsigned long ceiling)
+{
+	pmd_t *pmdp, pmd;
+	unsigned long i, next, start = addr;
+
+	do {
+		next = pmd_addr_end(addr, end);
+		pmdp = pmd_offset(pudp, addr);
+		pmd = READ_ONCE(*pmdp);
+		if (pmd_none(pmd))
+			continue;
+
+		WARN_ON(!pmd_present(pmd) || !pmd_table(pmd) || pmd_sect(pmd));
+		free_empty_pte_table(pmdp, addr, next, floor, ceiling);
+	} while (addr = next, addr < end);
+
+	if (CONFIG_PGTABLE_LEVELS <= 2)
+		return;
+
+	if (!pgtable_range_aligned(start, end, floor, ceiling, PUD_MASK))
+		return;
+
+	/*
+	 * Check whether we can free the pmd page if the rest of the
+	 * entries are empty. Overlap with other regions have been
+	 * handled by the floor/ceiling check.
+	 */
+	pmdp = pmd_offset(pudp, 0UL);
+	for (i = 0; i < PTRS_PER_PMD; i++) {
+		if (!pmd_none(READ_ONCE(pmdp[i])))
+			return;
+	}
+
+	pud_clear(pudp);
+	__flush_tlb_kernel_pgtable(start);
+	free_hotplug_pgtable_page(virt_to_page(pmdp));
+}
+
+static void free_empty_pud_table(p4d_t *p4dp, unsigned long addr,
+				 unsigned long end, unsigned long floor,
+				 unsigned long ceiling)
+{
+	pud_t *pudp, pud;
+	unsigned long i, next, start = addr;
+
+	do {
+		next = pud_addr_end(addr, end);
+		pudp = pud_offset(p4dp, addr);
+		pud = READ_ONCE(*pudp);
+		if (pud_none(pud))
+			continue;
+
+		WARN_ON(!pud_present(pud) || !pud_table(pud) || pud_sect(pud));
+		free_empty_pmd_table(pudp, addr, next, floor, ceiling);
+	} while (addr = next, addr < end);
+
+	if (CONFIG_PGTABLE_LEVELS <= 3)
+		return;
+
+	if (!pgtable_range_aligned(start, end, floor, ceiling, PGDIR_MASK))
+		return;
+
+	/*
+	 * Check whether we can free the pud page if the rest of the
+	 * entries are empty. Overlap with other regions have been
+	 * handled by the floor/ceiling check.
+	 */
+	pudp = pud_offset(p4dp, 0UL);
+	for (i = 0; i < PTRS_PER_PUD; i++) {
+		if (!pud_none(READ_ONCE(pudp[i])))
+			return;
+	}
+
+	p4d_clear(p4dp);
+	__flush_tlb_kernel_pgtable(start);
+	free_hotplug_pgtable_page(virt_to_page(pudp));
+}
+
+static void free_empty_p4d_table(pgd_t *pgdp, unsigned long addr,
+				 unsigned long end, unsigned long floor,
+				 unsigned long ceiling)
+{
+	unsigned long next;
+	p4d_t *p4dp, p4d;
+
+	do {
+		next = p4d_addr_end(addr, end);
+		p4dp = p4d_offset(pgdp, addr);
+		p4d = READ_ONCE(*p4dp);
+		if (p4d_none(p4d))
+			continue;
+
+		WARN_ON(!p4d_present(p4d));
+		free_empty_pud_table(p4dp, addr, next, floor, ceiling);
+	} while (addr = next, addr < end);
+}
+
+static void free_empty_tables(unsigned long addr, unsigned long end,
+			      unsigned long floor, unsigned long ceiling)
+{
+	unsigned long next;
+	pgd_t *pgdp, pgd;
+
+	do {
+		next = pgd_addr_end(addr, end);
+		pgdp = pgd_offset_k(addr);
+		pgd = READ_ONCE(*pgdp);
+		if (pgd_none(pgd))
+			continue;
+
+		WARN_ON(!pgd_present(pgd));
+		free_empty_p4d_table(pgdp, addr, next, floor, ceiling);
+	} while (addr = next, addr < end);
+}
+#endif
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+#if !ARM64_SWAPPER_USES_SECTION_MAPS
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
+{
+	return vmemmap_populate_basepages(start, end, node, altmap);
+}
+#else	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+		struct vmem_altmap *altmap)
+{
+	unsigned long addr = start;
+	unsigned long next;
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+
+	do {
+		next = pmd_addr_end(addr, end);
+
+		pgdp = vmemmap_pgd_populate(addr, node);
+		if (!pgdp)
+			return -ENOMEM;
+
+		p4dp = vmemmap_p4d_populate(pgdp, addr, node);
+		if (!p4dp)
+			return -ENOMEM;
+
+		pudp = vmemmap_pud_populate(p4dp, addr, node);
+		if (!pudp)
+			return -ENOMEM;
+
+		pmdp = pmd_offset(pudp, addr);
+		if (pmd_none(READ_ONCE(*pmdp))) {
+			void *p = NULL;
+
+			p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
+			if (!p)
+				return -ENOMEM;
+
+			pmd_set_huge(pmdp, __pa(p), __pgprot(PROT_SECT_NORMAL));
+		} else
+			vmemmap_verify((pte_t *)pmdp, node, addr, next);
+	} while (addr = next, addr != end);
+
+	return 0;
+}
+#endif	/* !ARM64_SWAPPER_USES_SECTION_MAPS */
+void vmemmap_free(unsigned long start, unsigned long end,
+		struct vmem_altmap *altmap)
+{
+#ifdef CONFIG_MEMORY_HOTPLUG
+	WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END));
+
+	unmap_hotplug_range(start, end, true, altmap);
+	free_empty_tables(start, end, VMEMMAP_START, VMEMMAP_END);
+#endif
+}
+#endif	/* CONFIG_SPARSEMEM_VMEMMAP */
+
+static inline pud_t * fixmap_pud(unsigned long addr)
+{
+	pgd_t *pgdp = pgd_offset_k(addr);
+	p4d_t *p4dp = p4d_offset(pgdp, addr);
+	p4d_t p4d = READ_ONCE(*p4dp);
+
+	BUG_ON(p4d_none(p4d) || p4d_bad(p4d));
+
+	return pud_offset_kimg(p4dp, addr);
+}
+
+static inline pmd_t * fixmap_pmd(unsigned long addr)
+{
+	pud_t *pudp = fixmap_pud(addr);
+	pud_t pud = READ_ONCE(*pudp);
+
+	BUG_ON(pud_none(pud) || pud_bad(pud));
+
+	return pmd_offset_kimg(pudp, addr);
+}
+
+static inline pte_t * fixmap_pte(unsigned long addr)
+{
+	return &bm_pte[pte_index(addr)];
+}
+
+/*
+ * The p*d_populate functions call virt_to_phys implicitly so they can't be used
+ * directly on kernel symbols (bm_p*d). This function is called too early to use
+ * lm_alias so __p*d_populate functions must be used to populate with the
+ * physical address from __pa_symbol.
+ */
+void __init early_fixmap_init(void)
+{
+	pgd_t *pgdp;
+	p4d_t *p4dp, p4d;
+	pud_t *pudp;
+	pmd_t *pmdp;
+	unsigned long addr = FIXADDR_START;
+
+	pgdp = pgd_offset_k(addr);
+	p4dp = p4d_offset(pgdp, addr);
+	p4d = READ_ONCE(*p4dp);
+	if (CONFIG_PGTABLE_LEVELS > 3 &&
+	    !(p4d_none(p4d) || p4d_page_paddr(p4d) == __pa_symbol(bm_pud))) {
+		/*
+		 * We only end up here if the kernel mapping and the fixmap
+		 * share the top level pgd entry, which should only happen on
+		 * 16k/4 levels configurations.
+		 */
+		BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
+		pudp = pud_offset_kimg(p4dp, addr);
+	} else {
+		if (p4d_none(p4d))
+			__p4d_populate(p4dp, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
+		pudp = fixmap_pud(addr);
+	}
+	if (pud_none(READ_ONCE(*pudp)))
+		__pud_populate(pudp, __pa_symbol(bm_pmd), PMD_TYPE_TABLE);
+	pmdp = fixmap_pmd(addr);
+	__pmd_populate(pmdp, __pa_symbol(bm_pte), PMD_TYPE_TABLE);
+
+	/*
+	 * The boot-ioremap range spans multiple pmds, for which
+	 * we are not prepared:
+	 */
+	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
+		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
+
+	if ((pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)))
+	     || pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) {
+		WARN_ON(1);
+		pr_warn("pmdp %p != %p, %p\n",
+			pmdp, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)),
+			fixmap_pmd(fix_to_virt(FIX_BTMAP_END)));
+		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
+			fix_to_virt(FIX_BTMAP_BEGIN));
+		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
+			fix_to_virt(FIX_BTMAP_END));
+
+		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
+		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
+	}
+}
+
+/*
+ * Unusually, this is also called in IRQ context (ghes_iounmap_irq) so if we
+ * ever need to use IPIs for TLB broadcasting, then we're in trouble here.
+ */
+void __set_fixmap(enum fixed_addresses idx,
+			       phys_addr_t phys, pgprot_t flags)
+{
+	unsigned long addr = __fix_to_virt(idx);
+	pte_t *ptep;
+
+	BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
+
+	ptep = fixmap_pte(addr);
+
+	if (pgprot_val(flags)) {
+		set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
+	} else {
+		pte_clear(&init_mm, addr, ptep);
+		flush_tlb_kernel_range(addr, addr+PAGE_SIZE);
+	}
+}
+
+void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
+{
+	const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
+	int offset;
+	void *dt_virt;
+
+	/*
+	 * Check whether the physical FDT address is set and meets the minimum
+	 * alignment requirement. Since we are relying on MIN_FDT_ALIGN to be
+	 * at least 8 bytes so that we can always access the magic and size
+	 * fields of the FDT header after mapping the first chunk, double check
+	 * here if that is indeed the case.
+	 */
+	BUILD_BUG_ON(MIN_FDT_ALIGN < 8);
+	if (!dt_phys || dt_phys % MIN_FDT_ALIGN)
+		return NULL;
+
+	/*
+	 * Make sure that the FDT region can be mapped without the need to
+	 * allocate additional translation table pages, so that it is safe
+	 * to call create_mapping_noalloc() this early.
+	 *
+	 * On 64k pages, the FDT will be mapped using PTEs, so we need to
+	 * be in the same PMD as the rest of the fixmap.
+	 * On 4k pages, we'll use section mappings for the FDT so we only
+	 * have to be in the same PUD.
+	 */
+	BUILD_BUG_ON(dt_virt_base % SZ_2M);
+
+	BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT !=
+		     __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT);
+
+	offset = dt_phys % SWAPPER_BLOCK_SIZE;
+	dt_virt = (void *)dt_virt_base + offset;
+
+	/* map the first chunk so we can read the size from the header */
+	create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE),
+			dt_virt_base, SWAPPER_BLOCK_SIZE, prot);
+
+	if (fdt_magic(dt_virt) != FDT_MAGIC)
+		return NULL;
+
+	*size = fdt_totalsize(dt_virt);
+	if (*size > MAX_FDT_SIZE)
+		return NULL;
+
+	if (offset + *size > SWAPPER_BLOCK_SIZE)
+		create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
+			       round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot);
+
+	return dt_virt;
+}
+
+int __init arch_ioremap_p4d_supported(void)
+{
+	return 0;
+}
+
+int __init arch_ioremap_pud_supported(void)
+{
+	/*
+	 * Only 4k granule supports level 1 block mappings.
+	 * SW table walks can't handle removal of intermediate entries.
+	 */
+	return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
+	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
+
+int __init arch_ioremap_pmd_supported(void)
+{
+	/* See arch_ioremap_pud_supported() */
+	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
+
+int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot)
+{
+	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), mk_pud_sect_prot(prot));
+
+	/* Only allow permission changes for now */
+	if (!pgattr_change_is_safe(READ_ONCE(pud_val(*pudp)),
+				   pud_val(new_pud)))
+		return 0;
+
+	VM_BUG_ON(phys & ~PUD_MASK);
+	set_pud(pudp, new_pud);
+	return 1;
+}
+
+int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot)
+{
+	pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), mk_pmd_sect_prot(prot));
+
+	/* Only allow permission changes for now */
+	if (!pgattr_change_is_safe(READ_ONCE(pmd_val(*pmdp)),
+				   pmd_val(new_pmd)))
+		return 0;
+
+	VM_BUG_ON(phys & ~PMD_MASK);
+	set_pmd(pmdp, new_pmd);
+	return 1;
+}
+
+int pud_clear_huge(pud_t *pudp)
+{
+	if (!pud_sect(READ_ONCE(*pudp)))
+		return 0;
+	pud_clear(pudp);
+	return 1;
+}
+
+int pmd_clear_huge(pmd_t *pmdp)
+{
+	if (!pmd_sect(READ_ONCE(*pmdp)))
+		return 0;
+	pmd_clear(pmdp);
+	return 1;
+}
+
+int pmd_free_pte_page(pmd_t *pmdp, unsigned long addr)
+{
+	pte_t *table;
+	pmd_t pmd;
+
+	pmd = READ_ONCE(*pmdp);
+
+	if (!pmd_table(pmd)) {
+		VM_WARN_ON(1);
+		return 1;
+	}
+
+	table = pte_offset_kernel(pmdp, addr);
+	pmd_clear(pmdp);
+	__flush_tlb_kernel_pgtable(addr);
+	pte_free_kernel(NULL, table);
+	return 1;
+}
+
+int pud_free_pmd_page(pud_t *pudp, unsigned long addr)
+{
+	pmd_t *table;
+	pmd_t *pmdp;
+	pud_t pud;
+	unsigned long next, end;
+
+	pud = READ_ONCE(*pudp);
+
+	if (!pud_table(pud)) {
+		VM_WARN_ON(1);
+		return 1;
+	}
+
+	table = pmd_offset(pudp, addr);
+	pmdp = table;
+	next = addr;
+	end = addr + PUD_SIZE;
+	do {
+		pmd_free_pte_page(pmdp, next);
+	} while (pmdp++, next += PMD_SIZE, next != end);
+
+	pud_clear(pudp);
+	__flush_tlb_kernel_pgtable(addr);
+	pmd_free(NULL, table);
+	return 1;
+}
+
+int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
+{
+	return 0;	/* Don't attempt a block mapping */
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
+{
+	unsigned long end = start + size;
+
+	WARN_ON(pgdir != init_mm.pgd);
+	WARN_ON((start < PAGE_OFFSET) || (end > PAGE_END));
+
+	unmap_hotplug_range(start, end, false, NULL);
+	free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
+}
+
+static bool inside_linear_region(u64 start, u64 size)
+{
+	u64 start_linear_pa = __pa(_PAGE_OFFSET(vabits_actual));
+	u64 end_linear_pa = __pa(PAGE_END - 1);
+
+	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+		/*
+		 * Check for a wrap, it is possible because of randomized linear
+		 * mapping the start physical address is actually bigger than
+		 * the end physical address. In this case set start to zero
+		 * because [0, end_linear_pa] range must still be able to cover
+		 * all addressable physical addresses.
+		 */
+		if (start_linear_pa > end_linear_pa)
+			start_linear_pa = 0;
+	}
+
+	WARN_ON(start_linear_pa > end_linear_pa);
+
+	/*
+	 * Linear mapping region is the range [PAGE_OFFSET..(PAGE_END - 1)]
+	 * accommodating both its ends but excluding PAGE_END. Max physical
+	 * range which can be mapped inside this linear mapping range, must
+	 * also be derived from its end points.
+	 */
+	return start >= start_linear_pa && (start + size - 1) <= end_linear_pa;
+}
+
+int arch_add_memory(int nid, u64 start, u64 size,
+		    struct mhp_params *params)
+{
+	int ret, flags = 0;
+
+	if (!inside_linear_region(start, size)) {
+		pr_err("[%llx %llx] is outside linear mapping region\n", start, start + size);
+		return -EINVAL;
+	}
+
+	if (rodata_full || debug_pagealloc_enabled())
+		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
+
+	__create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start),
+			     size, params->pgprot, __pgd_pgtable_alloc,
+			     flags);
+
+	memblock_clear_nomap(start, size);
+
+	ret = __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT,
+			   params);
+	if (ret)
+		__remove_pgd_mapping(swapper_pg_dir,
+				     __phys_to_virt(start), size);
+	else {
+		max_pfn = PFN_UP(start + size);
+		max_low_pfn = max_pfn;
+	}
+
+	return ret;
+}
+
+void arch_remove_memory(int nid, u64 start, u64 size,
+			struct vmem_altmap *altmap)
+{
+	unsigned long start_pfn = start >> PAGE_SHIFT;
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+
+	__remove_pages(start_pfn, nr_pages, altmap);
+	__remove_pgd_mapping(swapper_pg_dir, __phys_to_virt(start), size);
+}
+
+/*
+ * This memory hotplug notifier helps prevent boot memory from being
+ * inadvertently removed as it blocks pfn range offlining process in
+ * __offline_pages(). Hence this prevents both offlining as well as
+ * removal process for boot memory which is initially always online.
+ * In future if and when boot memory could be removed, this notifier
+ * should be dropped and free_hotplug_page_range() should handle any
+ * reserved pages allocated during boot.
+ */
+static int prevent_bootmem_remove_notifier(struct notifier_block *nb,
+					   unsigned long action, void *data)
+{
+	struct mem_section *ms;
+	struct memory_notify *arg = data;
+	unsigned long end_pfn = arg->start_pfn + arg->nr_pages;
+	unsigned long pfn = arg->start_pfn;
+
+	if (action != MEM_GOING_OFFLINE)
+		return NOTIFY_OK;
+
+	for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+		ms = __pfn_to_section(pfn);
+		if (early_section(ms))
+			return NOTIFY_BAD;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block prevent_bootmem_remove_nb = {
+	.notifier_call = prevent_bootmem_remove_notifier,
+};
+
+static int __init prevent_bootmem_remove_init(void)
+{
+	return register_memory_notifier(&prevent_bootmem_remove_nb);
+}
+device_initcall(prevent_bootmem_remove_init);
+#endif
diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
new file mode 100644
index 000000000..c52c18470
--- /dev/null
+++ b/arch/arm64/mm/mteswap.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/pagemap.h>
+#include <linux/xarray.h>
+#include <linux/slab.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <asm/mte.h>
+
+static DEFINE_XARRAY(mte_pages);
+
+void *mte_allocate_tag_storage(void)
+{
+	/* tags granule is 16 bytes, 2 tags stored per byte */
+	return kmalloc(PAGE_SIZE / 16 / 2, GFP_KERNEL);
+}
+
+void mte_free_tag_storage(char *storage)
+{
+	kfree(storage);
+}
+
+int mte_save_tags(struct page *page)
+{
+	void *tag_storage, *ret;
+
+	if (!test_bit(PG_mte_tagged, &page->flags))
+		return 0;
+
+	tag_storage = mte_allocate_tag_storage();
+	if (!tag_storage)
+		return -ENOMEM;
+
+	mte_save_page_tags(page_address(page), tag_storage);
+
+	/* page_private contains the swap entry.val set in do_swap_page */
+	ret = xa_store(&mte_pages, page_private(page), tag_storage, GFP_KERNEL);
+	if (WARN(xa_is_err(ret), "Failed to store MTE tags")) {
+		mte_free_tag_storage(tag_storage);
+		return xa_err(ret);
+	} else if (ret) {
+		/* Entry is being replaced, free the old entry */
+		mte_free_tag_storage(ret);
+	}
+
+	return 0;
+}
+
+bool mte_restore_tags(swp_entry_t entry, struct page *page)
+{
+	void *tags = xa_load(&mte_pages, entry.val);
+
+	if (!tags)
+		return false;
+
+	mte_restore_page_tags(page_address(page), tags);
+
+	return true;
+}
+
+void mte_invalidate_tags(int type, pgoff_t offset)
+{
+	swp_entry_t entry = swp_entry(type, offset);
+	void *tags = xa_erase(&mte_pages, entry.val);
+
+	mte_free_tag_storage(tags);
+}
+
+void mte_invalidate_tags_area(int type)
+{
+	swp_entry_t entry = swp_entry(type, 0);
+	swp_entry_t last_entry = swp_entry(type + 1, 0);
+	void *tags;
+
+	XA_STATE(xa_state, &mte_pages, entry.val);
+
+	xa_lock(&mte_pages);
+	xas_for_each(&xa_state, tags, last_entry.val - 1) {
+		__xa_erase(&mte_pages, xa_state.xa_index);
+		mte_free_tag_storage(tags);
+	}
+	xa_unlock(&mte_pages);
+}
diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
new file mode 100644
index 000000000..a8303bc6b
--- /dev/null
+++ b/arch/arm64/mm/numa.c
@@ -0,0 +1,464 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NUMA support, based on the x86 implementation.
+ *
+ * Copyright (C) 2015 Cavium Inc.
+ * Author: Ganapatrao Kulkarni <gkulkarni@cavium.com>
+ */
+
+#define pr_fmt(fmt) "NUMA: " fmt
+
+#include <linux/acpi.h>
+#include <linux/memblock.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <asm/acpi.h>
+#include <asm/sections.h>
+
+struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
+EXPORT_SYMBOL(node_data);
+nodemask_t numa_nodes_parsed __initdata;
+static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
+
+static int numa_distance_cnt;
+static u8 *numa_distance;
+bool numa_off;
+
+static __init int numa_parse_early_param(char *opt)
+{
+	if (!opt)
+		return -EINVAL;
+	if (str_has_prefix(opt, "off"))
+		numa_off = true;
+
+	return 0;
+}
+early_param("numa", numa_parse_early_param);
+
+cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
+EXPORT_SYMBOL(node_to_cpumask_map);
+
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+
+/*
+ * Returns a pointer to the bitmask of CPUs on Node 'node'.
+ */
+const struct cpumask *cpumask_of_node(int node)
+{
+
+	if (node == NUMA_NO_NODE)
+		return cpu_all_mask;
+
+	if (WARN_ON(node < 0 || node >= nr_node_ids))
+		return cpu_none_mask;
+
+	if (WARN_ON(node_to_cpumask_map[node] == NULL))
+		return cpu_online_mask;
+
+	return node_to_cpumask_map[node];
+}
+EXPORT_SYMBOL(cpumask_of_node);
+
+#endif
+
+static void numa_update_cpu(unsigned int cpu, bool remove)
+{
+	int nid = cpu_to_node(cpu);
+
+	if (nid == NUMA_NO_NODE)
+		return;
+
+	if (remove)
+		cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
+	else
+		cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
+}
+
+void numa_add_cpu(unsigned int cpu)
+{
+	numa_update_cpu(cpu, false);
+}
+
+void numa_remove_cpu(unsigned int cpu)
+{
+	numa_update_cpu(cpu, true);
+}
+
+void numa_clear_node(unsigned int cpu)
+{
+	numa_remove_cpu(cpu);
+	set_cpu_numa_node(cpu, NUMA_NO_NODE);
+}
+
+/*
+ * Allocate node_to_cpumask_map based on number of available nodes
+ * Requires node_possible_map to be valid.
+ *
+ * Note: cpumask_of_node() is not valid until after this is done.
+ * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
+ */
+static void __init setup_node_to_cpumask_map(void)
+{
+	int node;
+
+	/* setup nr_node_ids if not done yet */
+	if (nr_node_ids == MAX_NUMNODES)
+		setup_nr_node_ids();
+
+	/* allocate and clear the mapping */
+	for (node = 0; node < nr_node_ids; node++) {
+		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
+		cpumask_clear(node_to_cpumask_map[node]);
+	}
+
+	/* cpumask_of_node() will now work */
+	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
+}
+
+/*
+ * Set the cpu to node and mem mapping
+ */
+void numa_store_cpu_info(unsigned int cpu)
+{
+	set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
+}
+
+void __init early_map_cpu_to_node(unsigned int cpu, int nid)
+{
+	/* fallback to node 0 */
+	if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
+		nid = 0;
+
+	cpu_to_node_map[cpu] = nid;
+
+	/*
+	 * We should set the numa node of cpu0 as soon as possible, because it
+	 * has already been set up online before. cpu_to_node(0) will soon be
+	 * called.
+	 */
+	if (!cpu)
+		set_cpu_numa_node(cpu, nid);
+}
+
+#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
+unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
+EXPORT_SYMBOL(__per_cpu_offset);
+
+static int __init early_cpu_to_node(int cpu)
+{
+	return cpu_to_node_map[cpu];
+}
+
+static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
+{
+	return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
+}
+
+static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
+				       size_t align)
+{
+	int nid = early_cpu_to_node(cpu);
+
+	return  memblock_alloc_try_nid(size, align,
+			__pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, nid);
+}
+
+static void __init pcpu_fc_free(void *ptr, size_t size)
+{
+	memblock_free_early(__pa(ptr), size);
+}
+
+void __init setup_per_cpu_areas(void)
+{
+	unsigned long delta;
+	unsigned int cpu;
+	int rc;
+
+	/*
+	 * Always reserve area for module percpu variables.  That's
+	 * what the legacy allocator did.
+	 */
+	rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
+				    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
+				    pcpu_cpu_distance,
+				    pcpu_fc_alloc, pcpu_fc_free);
+	if (rc < 0)
+		panic("Failed to initialize percpu areas.");
+
+	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
+	for_each_possible_cpu(cpu)
+		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
+}
+#endif
+
+/**
+ * numa_add_memblk() - Set node id to memblk
+ * @nid: NUMA node ID of the new memblk
+ * @start: Start address of the new memblk
+ * @end:  End address of the new memblk
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int __init numa_add_memblk(int nid, u64 start, u64 end)
+{
+	int ret;
+
+	ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
+	if (ret < 0) {
+		pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
+			start, (end - 1), nid);
+		return ret;
+	}
+
+	node_set(nid, numa_nodes_parsed);
+	return ret;
+}
+
+/*
+ * Initialize NODE_DATA for a node on the local memory
+ */
+static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
+{
+	const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
+	u64 nd_pa;
+	void *nd;
+	int tnid;
+
+	if (start_pfn >= end_pfn)
+		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
+
+	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+	if (!nd_pa)
+		panic("Cannot allocate %zu bytes for node %d data\n",
+		      nd_size, nid);
+
+	nd = __va(nd_pa);
+
+	/* report and initialize */
+	pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
+		nd_pa, nd_pa + nd_size - 1);
+	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
+	if (tnid != nid)
+		pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
+
+	node_data[nid] = nd;
+	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
+	NODE_DATA(nid)->node_id = nid;
+	NODE_DATA(nid)->node_start_pfn = start_pfn;
+	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
+}
+
+/*
+ * numa_free_distance
+ *
+ * The current table is freed.
+ */
+void __init numa_free_distance(void)
+{
+	size_t size;
+
+	if (!numa_distance)
+		return;
+
+	size = numa_distance_cnt * numa_distance_cnt *
+		sizeof(numa_distance[0]);
+
+	memblock_free(__pa(numa_distance), size);
+	numa_distance_cnt = 0;
+	numa_distance = NULL;
+}
+
+/*
+ * Create a new NUMA distance table.
+ */
+static int __init numa_alloc_distance(void)
+{
+	size_t size;
+	u64 phys;
+	int i, j;
+
+	size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
+	phys = memblock_find_in_range(0, PFN_PHYS(max_pfn),
+				      size, PAGE_SIZE);
+	if (WARN_ON(!phys))
+		return -ENOMEM;
+
+	memblock_reserve(phys, size);
+
+	numa_distance = __va(phys);
+	numa_distance_cnt = nr_node_ids;
+
+	/* fill with the default distances */
+	for (i = 0; i < numa_distance_cnt; i++)
+		for (j = 0; j < numa_distance_cnt; j++)
+			numa_distance[i * numa_distance_cnt + j] = i == j ?
+				LOCAL_DISTANCE : REMOTE_DISTANCE;
+
+	pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
+
+	return 0;
+}
+
+/**
+ * numa_set_distance() - Set inter node NUMA distance from node to node.
+ * @from: the 'from' node to set distance
+ * @to: the 'to'  node to set distance
+ * @distance: NUMA distance
+ *
+ * Set the distance from node @from to @to to @distance.
+ * If distance table doesn't exist, a warning is printed.
+ *
+ * If @from or @to is higher than the highest known node or lower than zero
+ * or @distance doesn't make sense, the call is ignored.
+ */
+void __init numa_set_distance(int from, int to, int distance)
+{
+	if (!numa_distance) {
+		pr_warn_once("Warning: distance table not allocated yet\n");
+		return;
+	}
+
+	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
+			from < 0 || to < 0) {
+		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
+			    from, to, distance);
+		return;
+	}
+
+	if ((u8)distance != distance ||
+	    (from == to && distance != LOCAL_DISTANCE)) {
+		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
+			     from, to, distance);
+		return;
+	}
+
+	numa_distance[from * numa_distance_cnt + to] = distance;
+}
+
+/*
+ * Return NUMA distance @from to @to
+ */
+int __node_distance(int from, int to)
+{
+	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
+		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
+	return numa_distance[from * numa_distance_cnt + to];
+}
+EXPORT_SYMBOL(__node_distance);
+
+static int __init numa_register_nodes(void)
+{
+	int nid;
+	struct memblock_region *mblk;
+
+	/* Check that valid nid is set to memblks */
+	for_each_mem_region(mblk) {
+		int mblk_nid = memblock_get_region_node(mblk);
+
+		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
+			pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
+				mblk_nid, mblk->base,
+				mblk->base + mblk->size - 1);
+			return -EINVAL;
+		}
+	}
+
+	/* Finally register nodes. */
+	for_each_node_mask(nid, numa_nodes_parsed) {
+		unsigned long start_pfn, end_pfn;
+
+		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
+		setup_node_data(nid, start_pfn, end_pfn);
+		node_set_online(nid);
+	}
+
+	/* Setup online nodes to actual nodes*/
+	node_possible_map = numa_nodes_parsed;
+
+	return 0;
+}
+
+static int __init numa_init(int (*init_func)(void))
+{
+	int ret;
+
+	nodes_clear(numa_nodes_parsed);
+	nodes_clear(node_possible_map);
+	nodes_clear(node_online_map);
+
+	ret = numa_alloc_distance();
+	if (ret < 0)
+		return ret;
+
+	ret = init_func();
+	if (ret < 0)
+		goto out_free_distance;
+
+	if (nodes_empty(numa_nodes_parsed)) {
+		pr_info("No NUMA configuration found\n");
+		ret = -EINVAL;
+		goto out_free_distance;
+	}
+
+	ret = numa_register_nodes();
+	if (ret < 0)
+		goto out_free_distance;
+
+	setup_node_to_cpumask_map();
+
+	return 0;
+out_free_distance:
+	numa_free_distance();
+	return ret;
+}
+
+/**
+ * dummy_numa_init() - Fallback dummy NUMA init
+ *
+ * Used if there's no underlying NUMA architecture, NUMA initialization
+ * fails, or NUMA is disabled on the command line.
+ *
+ * Must online at least one node (node 0) and add memory blocks that cover all
+ * allowed memory. It is unlikely that this function fails.
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+static int __init dummy_numa_init(void)
+{
+	phys_addr_t start = memblock_start_of_DRAM();
+	phys_addr_t end = memblock_end_of_DRAM();
+	int ret;
+
+	if (numa_off)
+		pr_info("NUMA disabled\n"); /* Forced off on command line. */
+	pr_info("Faking a node at [mem %#018Lx-%#018Lx]\n", start, end - 1);
+
+	ret = numa_add_memblk(0, start, end);
+	if (ret) {
+		pr_err("NUMA init failed\n");
+		return ret;
+	}
+
+	numa_off = true;
+	return 0;
+}
+
+/**
+ * arm64_numa_init() - Initialize NUMA
+ *
+ * Try each configured NUMA initialization method until one succeeds. The
+ * last fallback is dummy single node config encompassing whole memory.
+ */
+void __init arm64_numa_init(void)
+{
+	if (!numa_off) {
+		if (!acpi_disabled && !numa_init(arm64_acpi_numa_init))
+			return;
+		if (acpi_disabled && !numa_init(of_numa_init))
+			return;
+	}
+
+	numa_init(dummy_numa_init);
+}
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
new file mode 100644
index 000000000..1b94f5b82
--- /dev/null
+++ b/arch/arm64/mm/pageattr.c
@@ -0,0 +1,234 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ */
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/vmalloc.h>
+
+#include <asm/cacheflush.h>
+#include <asm/set_memory.h>
+#include <asm/tlbflush.h>
+
+struct page_change_data {
+	pgprot_t set_mask;
+	pgprot_t clear_mask;
+};
+
+bool rodata_full __ro_after_init = IS_ENABLED(CONFIG_RODATA_FULL_DEFAULT_ENABLED);
+
+static int change_page_range(pte_t *ptep, unsigned long addr, void *data)
+{
+	struct page_change_data *cdata = data;
+	pte_t pte = READ_ONCE(*ptep);
+
+	pte = clear_pte_bit(pte, cdata->clear_mask);
+	pte = set_pte_bit(pte, cdata->set_mask);
+
+	set_pte(ptep, pte);
+	return 0;
+}
+
+/*
+ * This function assumes that the range is mapped with PAGE_SIZE pages.
+ */
+static int __change_memory_common(unsigned long start, unsigned long size,
+				pgprot_t set_mask, pgprot_t clear_mask)
+{
+	struct page_change_data data;
+	int ret;
+
+	data.set_mask = set_mask;
+	data.clear_mask = clear_mask;
+
+	ret = apply_to_page_range(&init_mm, start, size, change_page_range,
+					&data);
+
+	flush_tlb_kernel_range(start, start + size);
+	return ret;
+}
+
+static int change_memory_common(unsigned long addr, int numpages,
+				pgprot_t set_mask, pgprot_t clear_mask)
+{
+	unsigned long start = addr;
+	unsigned long size = PAGE_SIZE * numpages;
+	unsigned long end = start + size;
+	struct vm_struct *area;
+	int i;
+
+	if (!PAGE_ALIGNED(addr)) {
+		start &= PAGE_MASK;
+		end = start + size;
+		WARN_ON_ONCE(1);
+	}
+
+	/*
+	 * Kernel VA mappings are always live, and splitting live section
+	 * mappings into page mappings may cause TLB conflicts. This means
+	 * we have to ensure that changing the permission bits of the range
+	 * we are operating on does not result in such splitting.
+	 *
+	 * Let's restrict ourselves to mappings created by vmalloc (or vmap).
+	 * Those are guaranteed to consist entirely of page mappings, and
+	 * splitting is never needed.
+	 *
+	 * So check whether the [addr, addr + size) interval is entirely
+	 * covered by precisely one VM area that has the VM_ALLOC flag set.
+	 */
+	area = find_vm_area((void *)addr);
+	if (!area ||
+	    end > (unsigned long)area->addr + area->size ||
+	    !(area->flags & VM_ALLOC))
+		return -EINVAL;
+
+	if (!numpages)
+		return 0;
+
+	/*
+	 * If we are manipulating read-only permissions, apply the same
+	 * change to the linear mapping of the pages that back this VM area.
+	 */
+	if (rodata_full && (pgprot_val(set_mask) == PTE_RDONLY ||
+			    pgprot_val(clear_mask) == PTE_RDONLY)) {
+		for (i = 0; i < area->nr_pages; i++) {
+			__change_memory_common((u64)page_address(area->pages[i]),
+					       PAGE_SIZE, set_mask, clear_mask);
+		}
+	}
+
+	/*
+	 * Get rid of potentially aliasing lazily unmapped vm areas that may
+	 * have permissions set that deviate from the ones we are setting here.
+	 */
+	vm_unmap_aliases();
+
+	return __change_memory_common(start, size, set_mask, clear_mask);
+}
+
+int set_memory_ro(unsigned long addr, int numpages)
+{
+	return change_memory_common(addr, numpages,
+					__pgprot(PTE_RDONLY),
+					__pgprot(PTE_WRITE));
+}
+
+int set_memory_rw(unsigned long addr, int numpages)
+{
+	return change_memory_common(addr, numpages,
+					__pgprot(PTE_WRITE),
+					__pgprot(PTE_RDONLY));
+}
+
+int set_memory_nx(unsigned long addr, int numpages)
+{
+	return change_memory_common(addr, numpages,
+					__pgprot(PTE_PXN),
+					__pgprot(PTE_MAYBE_GP));
+}
+
+int set_memory_x(unsigned long addr, int numpages)
+{
+	return change_memory_common(addr, numpages,
+					__pgprot(PTE_MAYBE_GP),
+					__pgprot(PTE_PXN));
+}
+
+int set_memory_valid(unsigned long addr, int numpages, int enable)
+{
+	if (enable)
+		return __change_memory_common(addr, PAGE_SIZE * numpages,
+					__pgprot(PTE_VALID),
+					__pgprot(0));
+	else
+		return __change_memory_common(addr, PAGE_SIZE * numpages,
+					__pgprot(0),
+					__pgprot(PTE_VALID));
+}
+
+int set_direct_map_invalid_noflush(struct page *page)
+{
+	struct page_change_data data = {
+		.set_mask = __pgprot(0),
+		.clear_mask = __pgprot(PTE_VALID),
+	};
+
+	if (!rodata_full)
+		return 0;
+
+	return apply_to_page_range(&init_mm,
+				   (unsigned long)page_address(page),
+				   PAGE_SIZE, change_page_range, &data);
+}
+
+int set_direct_map_default_noflush(struct page *page)
+{
+	struct page_change_data data = {
+		.set_mask = __pgprot(PTE_VALID | PTE_WRITE),
+		.clear_mask = __pgprot(PTE_RDONLY),
+	};
+
+	if (!rodata_full)
+		return 0;
+
+	return apply_to_page_range(&init_mm,
+				   (unsigned long)page_address(page),
+				   PAGE_SIZE, change_page_range, &data);
+}
+
+void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+	if (!debug_pagealloc_enabled() && !rodata_full)
+		return;
+
+	set_memory_valid((unsigned long)page_address(page), numpages, enable);
+}
+
+/*
+ * This function is used to determine if a linear map page has been marked as
+ * not-valid. Walk the page table and check the PTE_VALID bit. This is based
+ * on kern_addr_valid(), which almost does what we need.
+ *
+ * Because this is only called on the kernel linear map,  p?d_sect() implies
+ * p?d_present(). When debug_pagealloc is enabled, sections mappings are
+ * disabled.
+ */
+bool kernel_page_present(struct page *page)
+{
+	pgd_t *pgdp;
+	p4d_t *p4dp;
+	pud_t *pudp, pud;
+	pmd_t *pmdp, pmd;
+	pte_t *ptep;
+	unsigned long addr = (unsigned long)page_address(page);
+
+	if (!debug_pagealloc_enabled() && !rodata_full)
+		return true;
+
+	pgdp = pgd_offset_k(addr);
+	if (pgd_none(READ_ONCE(*pgdp)))
+		return false;
+
+	p4dp = p4d_offset(pgdp, addr);
+	if (p4d_none(READ_ONCE(*p4dp)))
+		return false;
+
+	pudp = pud_offset(p4dp, addr);
+	pud = READ_ONCE(*pudp);
+	if (pud_none(pud))
+		return false;
+	if (pud_sect(pud))
+		return true;
+
+	pmdp = pmd_offset(pudp, addr);
+	pmd = READ_ONCE(*pmdp);
+	if (pmd_none(pmd))
+		return false;
+	if (pmd_sect(pmd))
+		return true;
+
+	ptep = pte_offset_kernel(pmdp, addr);
+	return pte_valid(READ_ONCE(*ptep));
+}
diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c
new file mode 100644
index 000000000..4a64089e5
--- /dev/null
+++ b/arch/arm64/mm/pgd.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PGD allocation/freeing
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+
+static struct kmem_cache *pgd_cache __ro_after_init;
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	gfp_t gfp = GFP_PGTABLE_USER;
+
+	if (PGD_SIZE == PAGE_SIZE)
+		return (pgd_t *)__get_free_page(gfp);
+	else
+		return kmem_cache_alloc(pgd_cache, gfp);
+}
+
+void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+	if (PGD_SIZE == PAGE_SIZE)
+		free_page((unsigned long)pgd);
+	else
+		kmem_cache_free(pgd_cache, pgd);
+}
+
+void __init pgtable_cache_init(void)
+{
+	if (PGD_SIZE == PAGE_SIZE)
+		return;
+
+#ifdef CONFIG_ARM64_PA_BITS_52
+	/*
+	 * With 52-bit physical addresses, the architecture requires the
+	 * top-level table to be aligned to at least 64 bytes.
+	 */
+	BUILD_BUG_ON(PGD_SIZE < 64);
+#endif
+
+	/*
+	 * Naturally aligned pgds required by the architecture.
+	 */
+	pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE,
+				      SLAB_PANIC, NULL);
+}
diff --git a/arch/arm64/mm/physaddr.c b/arch/arm64/mm/physaddr.c
new file mode 100644
index 000000000..cde44c13d
--- /dev/null
+++ b/arch/arm64/mm/physaddr.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/mmdebug.h>
+#include <linux/mm.h>
+
+#include <asm/memory.h>
+
+phys_addr_t __virt_to_phys(unsigned long x)
+{
+	WARN(!__is_lm_address(__tag_reset(x)),
+	     "virt_to_phys used for non-linear address: %pK (%pS)\n",
+	      (void *)x,
+	      (void *)x);
+
+	return __virt_to_phys_nodebug(x);
+}
+EXPORT_SYMBOL(__virt_to_phys);
+
+phys_addr_t __phys_addr_symbol(unsigned long x)
+{
+	/*
+	 * This is bounds checking against the kernel image only.
+	 * __pa_symbol should only be used on kernel symbol addresses.
+	 */
+	VIRTUAL_BUG_ON(x < (unsigned long) KERNEL_START ||
+		       x > (unsigned long) KERNEL_END);
+	return __pa_symbol_nodebug(x);
+}
+EXPORT_SYMBOL(__phys_addr_symbol);
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
new file mode 100644
index 000000000..aacc7eab9
--- /dev/null
+++ b/arch/arm64/mm/proc.S
@@ -0,0 +1,506 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Based on arch/arm/mm/proc.S
+ *
+ * Copyright (C) 2001 Deep Blue Solutions Ltd.
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/pgtable.h>
+#include <asm/assembler.h>
+#include <asm/asm-offsets.h>
+#include <asm/asm_pointer_auth.h>
+#include <asm/hwcap.h>
+#include <asm/pgtable-hwdef.h>
+#include <asm/cpufeature.h>
+#include <asm/alternative.h>
+#include <asm/smp.h>
+#include <asm/sysreg.h>
+
+#ifdef CONFIG_ARM64_64K_PAGES
+#define TCR_TG_FLAGS	TCR_TG0_64K | TCR_TG1_64K
+#elif defined(CONFIG_ARM64_16K_PAGES)
+#define TCR_TG_FLAGS	TCR_TG0_16K | TCR_TG1_16K
+#else /* CONFIG_ARM64_4K_PAGES */
+#define TCR_TG_FLAGS	TCR_TG0_4K | TCR_TG1_4K
+#endif
+
+#ifdef CONFIG_RANDOMIZE_BASE
+#define TCR_KASLR_FLAGS	TCR_NFD1
+#else
+#define TCR_KASLR_FLAGS	0
+#endif
+
+#define TCR_SMP_FLAGS	TCR_SHARED
+
+/* PTWs cacheable, inner/outer WBWA */
+#define TCR_CACHE_FLAGS	TCR_IRGN_WBWA | TCR_ORGN_WBWA
+
+#ifdef CONFIG_KASAN_SW_TAGS
+#define TCR_KASAN_FLAGS TCR_TBI1
+#else
+#define TCR_KASAN_FLAGS 0
+#endif
+
+/*
+ * Default MAIR_EL1. MT_NORMAL_TAGGED is initially mapped as Normal memory and
+ * changed during __cpu_setup to Normal Tagged if the system supports MTE.
+ */
+#define MAIR_EL1_SET							\
+	(MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRnE, MT_DEVICE_nGnRnE) |	\
+	 MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRE, MT_DEVICE_nGnRE) |	\
+	 MAIR_ATTRIDX(MAIR_ATTR_DEVICE_GRE, MT_DEVICE_GRE) |		\
+	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL_NC, MT_NORMAL_NC) |		\
+	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL) |			\
+	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL_WT, MT_NORMAL_WT) |		\
+	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL_TAGGED))
+
+#ifdef CONFIG_CPU_PM
+/**
+ * cpu_do_suspend - save CPU registers context
+ *
+ * x0: virtual address of context pointer
+ *
+ * This must be kept in sync with struct cpu_suspend_ctx in <asm/suspend.h>.
+ */
+SYM_FUNC_START(cpu_do_suspend)
+	mrs	x2, tpidr_el0
+	mrs	x3, tpidrro_el0
+	mrs	x4, contextidr_el1
+	mrs	x5, osdlr_el1
+	mrs	x6, cpacr_el1
+	mrs	x7, tcr_el1
+	mrs	x8, vbar_el1
+	mrs	x9, mdscr_el1
+	mrs	x10, oslsr_el1
+	mrs	x11, sctlr_el1
+alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
+	mrs	x12, tpidr_el1
+alternative_else
+	mrs	x12, tpidr_el2
+alternative_endif
+	mrs	x13, sp_el0
+	stp	x2, x3, [x0]
+	stp	x4, x5, [x0, #16]
+	stp	x6, x7, [x0, #32]
+	stp	x8, x9, [x0, #48]
+	stp	x10, x11, [x0, #64]
+	stp	x12, x13, [x0, #80]
+	/*
+	 * Save x18 as it may be used as a platform register, e.g. by shadow
+	 * call stack.
+	 */
+	str	x18, [x0, #96]
+	ret
+SYM_FUNC_END(cpu_do_suspend)
+
+/**
+ * cpu_do_resume - restore CPU register context
+ *
+ * x0: Address of context pointer
+ */
+	.pushsection ".idmap.text", "awx"
+SYM_FUNC_START(cpu_do_resume)
+	ldp	x2, x3, [x0]
+	ldp	x4, x5, [x0, #16]
+	ldp	x6, x8, [x0, #32]
+	ldp	x9, x10, [x0, #48]
+	ldp	x11, x12, [x0, #64]
+	ldp	x13, x14, [x0, #80]
+	/*
+	 * Restore x18, as it may be used as a platform register, and clear
+	 * the buffer to minimize the risk of exposure when used for shadow
+	 * call stack.
+	 */
+	ldr	x18, [x0, #96]
+	str	xzr, [x0, #96]
+	msr	tpidr_el0, x2
+	msr	tpidrro_el0, x3
+	msr	contextidr_el1, x4
+	msr	cpacr_el1, x6
+
+	/* Don't change t0sz here, mask those bits when restoring */
+	mrs	x7, tcr_el1
+	bfi	x8, x7, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH
+
+	msr	tcr_el1, x8
+	msr	vbar_el1, x9
+
+	/*
+	 * __cpu_setup() cleared MDSCR_EL1.MDE and friends, before unmasking
+	 * debug exceptions. By restoring MDSCR_EL1 here, we may take a debug
+	 * exception. Mask them until local_daif_restore() in cpu_suspend()
+	 * resets them.
+	 */
+	disable_daif
+	msr	mdscr_el1, x10
+
+	msr	sctlr_el1, x12
+alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
+	msr	tpidr_el1, x13
+alternative_else
+	msr	tpidr_el2, x13
+alternative_endif
+	msr	sp_el0, x14
+	/*
+	 * Restore oslsr_el1 by writing oslar_el1
+	 */
+	msr	osdlr_el1, x5
+	ubfx	x11, x11, #1, #1
+	msr	oslar_el1, x11
+	reset_pmuserenr_el0 x0			// Disable PMU access from EL0
+	reset_amuserenr_el0 x0			// Disable AMU access from EL0
+
+alternative_if ARM64_HAS_RAS_EXTN
+	msr_s	SYS_DISR_EL1, xzr
+alternative_else_nop_endif
+
+	ptrauth_keys_install_kernel_nosync x14, x1, x2, x3
+	isb
+	ret
+SYM_FUNC_END(cpu_do_resume)
+	.popsection
+#endif
+
+	.pushsection ".idmap.text", "awx"
+
+.macro	__idmap_cpu_set_reserved_ttbr1, tmp1, tmp2
+	adrp	\tmp1, reserved_pg_dir
+	phys_to_ttbr \tmp2, \tmp1
+	offset_ttbr1 \tmp2, \tmp1
+	msr	ttbr1_el1, \tmp2
+	isb
+	tlbi	vmalle1
+	dsb	nsh
+	isb
+.endm
+
+/*
+ * void idmap_cpu_replace_ttbr1(phys_addr_t ttbr1)
+ *
+ * This is the low-level counterpart to cpu_replace_ttbr1, and should not be
+ * called by anything else. It can only be executed from a TTBR0 mapping.
+ */
+SYM_FUNC_START(idmap_cpu_replace_ttbr1)
+	save_and_disable_daif flags=x2
+
+	__idmap_cpu_set_reserved_ttbr1 x1, x3
+
+	offset_ttbr1 x0, x3
+	msr	ttbr1_el1, x0
+	isb
+
+	restore_daif x2
+
+	ret
+SYM_FUNC_END(idmap_cpu_replace_ttbr1)
+	.popsection
+
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+	.pushsection ".idmap.text", "awx"
+
+	.macro	__idmap_kpti_get_pgtable_ent, type
+	dc	cvac, cur_\()\type\()p		// Ensure any existing dirty
+	dmb	sy				// lines are written back before
+	ldr	\type, [cur_\()\type\()p]	// loading the entry
+	tbz	\type, #0, skip_\()\type	// Skip invalid and
+	tbnz	\type, #11, skip_\()\type	// non-global entries
+	.endm
+
+	.macro __idmap_kpti_put_pgtable_ent_ng, type
+	orr	\type, \type, #PTE_NG		// Same bit for blocks and pages
+	str	\type, [cur_\()\type\()p]	// Update the entry and ensure
+	dmb	sy				// that it is visible to all
+	dc	civac, cur_\()\type\()p		// CPUs.
+	.endm
+
+/*
+ * void __kpti_install_ng_mappings(int cpu, int num_cpus, phys_addr_t swapper)
+ *
+ * Called exactly once from stop_machine context by each CPU found during boot.
+ */
+__idmap_kpti_flag:
+	.long	1
+SYM_FUNC_START(idmap_kpti_install_ng_mappings)
+	cpu		.req	w0
+	num_cpus	.req	w1
+	swapper_pa	.req	x2
+	swapper_ttb	.req	x3
+	flag_ptr	.req	x4
+	cur_pgdp	.req	x5
+	end_pgdp	.req	x6
+	pgd		.req	x7
+	cur_pudp	.req	x8
+	end_pudp	.req	x9
+	pud		.req	x10
+	cur_pmdp	.req	x11
+	end_pmdp	.req	x12
+	pmd		.req	x13
+	cur_ptep	.req	x14
+	end_ptep	.req	x15
+	pte		.req	x16
+
+	mrs	swapper_ttb, ttbr1_el1
+	restore_ttbr1	swapper_ttb
+	adr	flag_ptr, __idmap_kpti_flag
+
+	cbnz	cpu, __idmap_kpti_secondary
+
+	/* We're the boot CPU. Wait for the others to catch up */
+	sevl
+1:	wfe
+	ldaxr	w17, [flag_ptr]
+	eor	w17, w17, num_cpus
+	cbnz	w17, 1b
+
+	/* We need to walk swapper, so turn off the MMU. */
+	pre_disable_mmu_workaround
+	mrs	x17, sctlr_el1
+	bic	x17, x17, #SCTLR_ELx_M
+	msr	sctlr_el1, x17
+	isb
+
+	/* Everybody is enjoying the idmap, so we can rewrite swapper. */
+	/* PGD */
+	mov	cur_pgdp, swapper_pa
+	add	end_pgdp, cur_pgdp, #(PTRS_PER_PGD * 8)
+do_pgd:	__idmap_kpti_get_pgtable_ent	pgd
+	tbnz	pgd, #1, walk_puds
+next_pgd:
+	__idmap_kpti_put_pgtable_ent_ng	pgd
+skip_pgd:
+	add	cur_pgdp, cur_pgdp, #8
+	cmp	cur_pgdp, end_pgdp
+	b.ne	do_pgd
+
+	/* Publish the updated tables and nuke all the TLBs */
+	dsb	sy
+	tlbi	vmalle1is
+	dsb	ish
+	isb
+
+	/* We're done: fire up the MMU again */
+	mrs	x17, sctlr_el1
+	orr	x17, x17, #SCTLR_ELx_M
+	msr	sctlr_el1, x17
+	isb
+
+	/*
+	 * Invalidate the local I-cache so that any instructions fetched
+	 * speculatively from the PoC are discarded, since they may have
+	 * been dynamically patched at the PoU.
+	 */
+	ic	iallu
+	dsb	nsh
+	isb
+
+	/* Set the flag to zero to indicate that we're all done */
+	str	wzr, [flag_ptr]
+	ret
+
+	/* PUD */
+walk_puds:
+	.if CONFIG_PGTABLE_LEVELS > 3
+	pte_to_phys	cur_pudp, pgd
+	add	end_pudp, cur_pudp, #(PTRS_PER_PUD * 8)
+do_pud:	__idmap_kpti_get_pgtable_ent	pud
+	tbnz	pud, #1, walk_pmds
+next_pud:
+	__idmap_kpti_put_pgtable_ent_ng	pud
+skip_pud:
+	add	cur_pudp, cur_pudp, 8
+	cmp	cur_pudp, end_pudp
+	b.ne	do_pud
+	b	next_pgd
+	.else /* CONFIG_PGTABLE_LEVELS <= 3 */
+	mov	pud, pgd
+	b	walk_pmds
+next_pud:
+	b	next_pgd
+	.endif
+
+	/* PMD */
+walk_pmds:
+	.if CONFIG_PGTABLE_LEVELS > 2
+	pte_to_phys	cur_pmdp, pud
+	add	end_pmdp, cur_pmdp, #(PTRS_PER_PMD * 8)
+do_pmd:	__idmap_kpti_get_pgtable_ent	pmd
+	tbnz	pmd, #1, walk_ptes
+next_pmd:
+	__idmap_kpti_put_pgtable_ent_ng	pmd
+skip_pmd:
+	add	cur_pmdp, cur_pmdp, #8
+	cmp	cur_pmdp, end_pmdp
+	b.ne	do_pmd
+	b	next_pud
+	.else /* CONFIG_PGTABLE_LEVELS <= 2 */
+	mov	pmd, pud
+	b	walk_ptes
+next_pmd:
+	b	next_pud
+	.endif
+
+	/* PTE */
+walk_ptes:
+	pte_to_phys	cur_ptep, pmd
+	add	end_ptep, cur_ptep, #(PTRS_PER_PTE * 8)
+do_pte:	__idmap_kpti_get_pgtable_ent	pte
+	__idmap_kpti_put_pgtable_ent_ng	pte
+skip_pte:
+	add	cur_ptep, cur_ptep, #8
+	cmp	cur_ptep, end_ptep
+	b.ne	do_pte
+	b	next_pmd
+
+	.unreq	cpu
+	.unreq	num_cpus
+	.unreq	swapper_pa
+	.unreq	cur_pgdp
+	.unreq	end_pgdp
+	.unreq	pgd
+	.unreq	cur_pudp
+	.unreq	end_pudp
+	.unreq	pud
+	.unreq	cur_pmdp
+	.unreq	end_pmdp
+	.unreq	pmd
+	.unreq	cur_ptep
+	.unreq	end_ptep
+	.unreq	pte
+
+	/* Secondary CPUs end up here */
+__idmap_kpti_secondary:
+	/* Uninstall swapper before surgery begins */
+	__idmap_cpu_set_reserved_ttbr1 x16, x17
+
+	/* Increment the flag to let the boot CPU we're ready */
+1:	ldxr	w16, [flag_ptr]
+	add	w16, w16, #1
+	stxr	w17, w16, [flag_ptr]
+	cbnz	w17, 1b
+
+	/* Wait for the boot CPU to finish messing around with swapper */
+	sevl
+1:	wfe
+	ldxr	w16, [flag_ptr]
+	cbnz	w16, 1b
+
+	/* All done, act like nothing happened */
+	offset_ttbr1 swapper_ttb, x16
+	msr	ttbr1_el1, swapper_ttb
+	isb
+	ret
+
+	.unreq	swapper_ttb
+	.unreq	flag_ptr
+SYM_FUNC_END(idmap_kpti_install_ng_mappings)
+	.popsection
+#endif
+
+/*
+ *	__cpu_setup
+ *
+ *	Initialise the processor for turning the MMU on.
+ *
+ * Output:
+ *	Return in x0 the value of the SCTLR_EL1 register.
+ */
+	.pushsection ".idmap.text", "awx"
+SYM_FUNC_START(__cpu_setup)
+	tlbi	vmalle1				// Invalidate local TLB
+	dsb	nsh
+
+	mov	x1, #3 << 20
+	msr	cpacr_el1, x1			// Enable FP/ASIMD
+	mov	x1, #1 << 12			// Reset mdscr_el1 and disable
+	msr	mdscr_el1, x1			// access to the DCC from EL0
+	isb					// Unmask debug exceptions now,
+	enable_dbg				// since this is per-cpu
+	reset_pmuserenr_el0 x1			// Disable PMU access from EL0
+	reset_amuserenr_el0 x1			// Disable AMU access from EL0
+
+	/*
+	 * Memory region attributes
+	 */
+	mov_q	x5, MAIR_EL1_SET
+#ifdef CONFIG_ARM64_MTE
+	/*
+	 * Update MAIR_EL1, GCR_EL1 and TFSR*_EL1 if MTE is supported
+	 * (ID_AA64PFR1_EL1[11:8] > 1).
+	 */
+	mrs	x10, ID_AA64PFR1_EL1
+	ubfx	x10, x10, #ID_AA64PFR1_MTE_SHIFT, #4
+	cmp	x10, #ID_AA64PFR1_MTE
+	b.lt	1f
+
+	/* Normal Tagged memory type at the corresponding MAIR index */
+	mov	x10, #MAIR_ATTR_NORMAL_TAGGED
+	bfi	x5, x10, #(8 *  MT_NORMAL_TAGGED), #8
+
+	/* initialize GCR_EL1: all non-zero tags excluded by default */
+	mov	x10, #(SYS_GCR_EL1_RRND | SYS_GCR_EL1_EXCL_MASK)
+	msr_s	SYS_GCR_EL1, x10
+
+	/*
+	 * If GCR_EL1.RRND=1 is implemented the same way as RRND=0, then
+	 * RGSR_EL1.SEED must be non-zero for IRG to produce
+	 * pseudorandom numbers. As RGSR_EL1 is UNKNOWN out of reset, we
+	 * must initialize it.
+	 */
+	mrs	x10, CNTVCT_EL0
+	ands	x10, x10, #SYS_RGSR_EL1_SEED_MASK
+	csinc	x10, x10, xzr, ne
+	lsl	x10, x10, #SYS_RGSR_EL1_SEED_SHIFT
+	msr_s	SYS_RGSR_EL1, x10
+
+	/* clear any pending tag check faults in TFSR*_EL1 */
+	msr_s	SYS_TFSR_EL1, xzr
+	msr_s	SYS_TFSRE0_EL1, xzr
+1:
+#endif
+	msr	mair_el1, x5
+	/*
+	 * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for
+	 * both user and kernel.
+	 */
+	mov_q	x10, TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
+			TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \
+			TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS
+	tcr_clear_errata_bits x10, x9, x5
+
+#ifdef CONFIG_ARM64_VA_BITS_52
+	ldr_l		x9, vabits_actual
+	sub		x9, xzr, x9
+	add		x9, x9, #64
+	tcr_set_t1sz	x10, x9
+#else
+	ldr_l		x9, idmap_t0sz
+#endif
+	tcr_set_t0sz	x10, x9
+
+	/*
+	 * Set the IPS bits in TCR_EL1.
+	 */
+	tcr_compute_pa_size x10, #TCR_IPS_SHIFT, x5, x6
+#ifdef CONFIG_ARM64_HW_AFDBM
+	/*
+	 * Enable hardware update of the Access Flags bit.
+	 * Hardware dirty bit management is enabled later,
+	 * via capabilities.
+	 */
+	mrs	x9, ID_AA64MMFR1_EL1
+	and	x9, x9, #0xf
+	cbz	x9, 1f
+	orr	x10, x10, #TCR_HA		// hardware Access flag update
+1:
+#endif	/* CONFIG_ARM64_HW_AFDBM */
+	msr	tcr_el1, x10
+	/*
+	 * Prepare SCTLR
+	 */
+	mov_q	x0, SCTLR_EL1_SET
+	ret					// return to head.S
+SYM_FUNC_END(__cpu_setup)
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
new file mode 100644
index 000000000..807dc634b
--- /dev/null
+++ b/arch/arm64/mm/ptdump.c
@@ -0,0 +1,393 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ * Debug helper to dump the current kernel pagetables of the system
+ * so that we can see what the various memory ranges are set to.
+ *
+ * Derived from x86 and arm implementation:
+ * (C) Copyright 2008 Intel Corporation
+ *
+ * Author: Arjan van de Ven <arjan@linux.intel.com>
+ */
+#include <linux/debugfs.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/ptdump.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+
+#include <asm/fixmap.h>
+#include <asm/kasan.h>
+#include <asm/memory.h>
+#include <asm/pgtable-hwdef.h>
+#include <asm/ptdump.h>
+
+
+enum address_markers_idx {
+	PAGE_OFFSET_NR = 0,
+	PAGE_END_NR,
+#ifdef CONFIG_KASAN
+	KASAN_START_NR,
+#endif
+};
+
+static struct addr_marker address_markers[] = {
+	{ PAGE_OFFSET,			"Linear Mapping start" },
+	{ 0 /* PAGE_END */,		"Linear Mapping end" },
+#ifdef CONFIG_KASAN
+	{ 0 /* KASAN_SHADOW_START */,	"Kasan shadow start" },
+	{ KASAN_SHADOW_END,		"Kasan shadow end" },
+#endif
+	{ BPF_JIT_REGION_START,		"BPF start" },
+	{ BPF_JIT_REGION_END,		"BPF end" },
+	{ MODULES_VADDR,		"Modules start" },
+	{ MODULES_END,			"Modules end" },
+	{ VMALLOC_START,		"vmalloc() area" },
+	{ VMALLOC_END,			"vmalloc() end" },
+	{ FIXADDR_START,		"Fixmap start" },
+	{ FIXADDR_TOP,			"Fixmap end" },
+	{ PCI_IO_START,			"PCI I/O start" },
+	{ PCI_IO_END,			"PCI I/O end" },
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+	{ VMEMMAP_START,		"vmemmap start" },
+	{ VMEMMAP_START + VMEMMAP_SIZE,	"vmemmap end" },
+#endif
+	{ -1,				NULL },
+};
+
+#define pt_dump_seq_printf(m, fmt, args...)	\
+({						\
+	if (m)					\
+		seq_printf(m, fmt, ##args);	\
+})
+
+#define pt_dump_seq_puts(m, fmt)	\
+({					\
+	if (m)				\
+		seq_printf(m, fmt);	\
+})
+
+/*
+ * The page dumper groups page table entries of the same type into a single
+ * description. It uses pg_state to track the range information while
+ * iterating over the pte entries. When the continuity is broken it then
+ * dumps out a description of the range.
+ */
+struct pg_state {
+	struct ptdump_state ptdump;
+	struct seq_file *seq;
+	const struct addr_marker *marker;
+	unsigned long start_address;
+	int level;
+	u64 current_prot;
+	bool check_wx;
+	unsigned long wx_pages;
+	unsigned long uxn_pages;
+};
+
+struct prot_bits {
+	u64		mask;
+	u64		val;
+	const char	*set;
+	const char	*clear;
+};
+
+static const struct prot_bits pte_bits[] = {
+	{
+		.mask	= PTE_VALID,
+		.val	= PTE_VALID,
+		.set	= " ",
+		.clear	= "F",
+	}, {
+		.mask	= PTE_USER,
+		.val	= PTE_USER,
+		.set	= "USR",
+		.clear	= "   ",
+	}, {
+		.mask	= PTE_RDONLY,
+		.val	= PTE_RDONLY,
+		.set	= "ro",
+		.clear	= "RW",
+	}, {
+		.mask	= PTE_PXN,
+		.val	= PTE_PXN,
+		.set	= "NX",
+		.clear	= "x ",
+	}, {
+		.mask	= PTE_SHARED,
+		.val	= PTE_SHARED,
+		.set	= "SHD",
+		.clear	= "   ",
+	}, {
+		.mask	= PTE_AF,
+		.val	= PTE_AF,
+		.set	= "AF",
+		.clear	= "  ",
+	}, {
+		.mask	= PTE_NG,
+		.val	= PTE_NG,
+		.set	= "NG",
+		.clear	= "  ",
+	}, {
+		.mask	= PTE_CONT,
+		.val	= PTE_CONT,
+		.set	= "CON",
+		.clear	= "   ",
+	}, {
+		.mask	= PTE_TABLE_BIT,
+		.val	= PTE_TABLE_BIT,
+		.set	= "   ",
+		.clear	= "BLK",
+	}, {
+		.mask	= PTE_UXN,
+		.val	= PTE_UXN,
+		.set	= "UXN",
+		.clear	= "   ",
+	}, {
+		.mask	= PTE_GP,
+		.val	= PTE_GP,
+		.set	= "GP",
+		.clear	= "  ",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_DEVICE_nGnRnE),
+		.set	= "DEVICE/nGnRnE",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_DEVICE_nGnRE),
+		.set	= "DEVICE/nGnRE",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_DEVICE_GRE),
+		.set	= "DEVICE/GRE",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_NORMAL_NC),
+		.set	= "MEM/NORMAL-NC",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_NORMAL),
+		.set	= "MEM/NORMAL",
+	}, {
+		.mask	= PTE_ATTRINDX_MASK,
+		.val	= PTE_ATTRINDX(MT_NORMAL_TAGGED),
+		.set	= "MEM/NORMAL-TAGGED",
+	}
+};
+
+struct pg_level {
+	const struct prot_bits *bits;
+	const char *name;
+	size_t num;
+	u64 mask;
+};
+
+static struct pg_level pg_level[] = {
+	{ /* pgd */
+		.name	= "PGD",
+		.bits	= pte_bits,
+		.num	= ARRAY_SIZE(pte_bits),
+	}, { /* p4d */
+		.name	= "P4D",
+		.bits	= pte_bits,
+		.num	= ARRAY_SIZE(pte_bits),
+	}, { /* pud */
+		.name	= (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD",
+		.bits	= pte_bits,
+		.num	= ARRAY_SIZE(pte_bits),
+	}, { /* pmd */
+		.name	= (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD",
+		.bits	= pte_bits,
+		.num	= ARRAY_SIZE(pte_bits),
+	}, { /* pte */
+		.name	= "PTE",
+		.bits	= pte_bits,
+		.num	= ARRAY_SIZE(pte_bits),
+	},
+};
+
+static void dump_prot(struct pg_state *st, const struct prot_bits *bits,
+			size_t num)
+{
+	unsigned i;
+
+	for (i = 0; i < num; i++, bits++) {
+		const char *s;
+
+		if ((st->current_prot & bits->mask) == bits->val)
+			s = bits->set;
+		else
+			s = bits->clear;
+
+		if (s)
+			pt_dump_seq_printf(st->seq, " %s", s);
+	}
+}
+
+static void note_prot_uxn(struct pg_state *st, unsigned long addr)
+{
+	if (!st->check_wx)
+		return;
+
+	if ((st->current_prot & PTE_UXN) == PTE_UXN)
+		return;
+
+	WARN_ONCE(1, "arm64/mm: Found non-UXN mapping at address %p/%pS\n",
+		  (void *)st->start_address, (void *)st->start_address);
+
+	st->uxn_pages += (addr - st->start_address) / PAGE_SIZE;
+}
+
+static void note_prot_wx(struct pg_state *st, unsigned long addr)
+{
+	if (!st->check_wx)
+		return;
+	if ((st->current_prot & PTE_RDONLY) == PTE_RDONLY)
+		return;
+	if ((st->current_prot & PTE_PXN) == PTE_PXN)
+		return;
+
+	WARN_ONCE(1, "arm64/mm: Found insecure W+X mapping at address %p/%pS\n",
+		  (void *)st->start_address, (void *)st->start_address);
+
+	st->wx_pages += (addr - st->start_address) / PAGE_SIZE;
+}
+
+static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
+		      u64 val)
+{
+	struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
+	static const char units[] = "KMGTPE";
+	u64 prot = 0;
+
+	if (level >= 0)
+		prot = val & pg_level[level].mask;
+
+	if (st->level == -1) {
+		st->level = level;
+		st->current_prot = prot;
+		st->start_address = addr;
+		pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
+	} else if (prot != st->current_prot || level != st->level ||
+		   addr >= st->marker[1].start_address) {
+		const char *unit = units;
+		unsigned long delta;
+
+		if (st->current_prot) {
+			note_prot_uxn(st, addr);
+			note_prot_wx(st, addr);
+		}
+
+		pt_dump_seq_printf(st->seq, "0x%016lx-0x%016lx   ",
+				   st->start_address, addr);
+
+		delta = (addr - st->start_address) >> 10;
+		while (!(delta & 1023) && unit[1]) {
+			delta >>= 10;
+			unit++;
+		}
+		pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit,
+				   pg_level[st->level].name);
+		if (st->current_prot && pg_level[st->level].bits)
+			dump_prot(st, pg_level[st->level].bits,
+				  pg_level[st->level].num);
+		pt_dump_seq_puts(st->seq, "\n");
+
+		if (addr >= st->marker[1].start_address) {
+			st->marker++;
+			pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
+		}
+
+		st->start_address = addr;
+		st->current_prot = prot;
+		st->level = level;
+	}
+
+	if (addr >= st->marker[1].start_address) {
+		st->marker++;
+		pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
+	}
+
+}
+
+void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
+{
+	unsigned long end = ~0UL;
+	struct pg_state st;
+
+	if (info->base_addr < TASK_SIZE_64)
+		end = TASK_SIZE_64;
+
+	st = (struct pg_state){
+		.seq = s,
+		.marker = info->markers,
+		.ptdump = {
+			.note_page = note_page,
+			.range = (struct ptdump_range[]){
+				{info->base_addr, end},
+				{0, 0}
+			}
+		}
+	};
+
+	ptdump_walk_pgd(&st.ptdump, info->mm, NULL);
+}
+
+static void ptdump_initialize(void)
+{
+	unsigned i, j;
+
+	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
+		if (pg_level[i].bits)
+			for (j = 0; j < pg_level[i].num; j++)
+				pg_level[i].mask |= pg_level[i].bits[j].mask;
+}
+
+static struct ptdump_info kernel_ptdump_info = {
+	.mm		= &init_mm,
+	.markers	= address_markers,
+	.base_addr	= PAGE_OFFSET,
+};
+
+void ptdump_check_wx(void)
+{
+	struct pg_state st = {
+		.seq = NULL,
+		.marker = (struct addr_marker[]) {
+			{ 0, NULL},
+			{ -1, NULL},
+		},
+		.level = -1,
+		.check_wx = true,
+		.ptdump = {
+			.note_page = note_page,
+			.range = (struct ptdump_range[]) {
+				{PAGE_OFFSET, ~0UL},
+				{0, 0}
+			}
+		}
+	};
+
+	ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
+
+	if (st.wx_pages || st.uxn_pages)
+		pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found, %lu non-UXN pages found\n",
+			st.wx_pages, st.uxn_pages);
+	else
+		pr_info("Checked W+X mappings: passed, no W+X pages found\n");
+}
+
+static int ptdump_init(void)
+{
+	address_markers[PAGE_END_NR].start_address = PAGE_END;
+#ifdef CONFIG_KASAN
+	address_markers[KASAN_START_NR].start_address = KASAN_SHADOW_START;
+#endif
+	ptdump_initialize();
+	ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables");
+	return 0;
+}
+device_initcall(ptdump_init);
diff --git a/arch/arm64/mm/ptdump_debugfs.c b/arch/arm64/mm/ptdump_debugfs.c
new file mode 100644
index 000000000..d29d722ec
--- /dev/null
+++ b/arch/arm64/mm/ptdump_debugfs.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/debugfs.h>
+#include <linux/memory_hotplug.h>
+#include <linux/seq_file.h>
+
+#include <asm/ptdump.h>
+
+static int ptdump_show(struct seq_file *m, void *v)
+{
+	struct ptdump_info *info = m->private;
+
+	get_online_mems();
+	ptdump_walk(m, info);
+	put_online_mems();
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(ptdump);
+
+void ptdump_debugfs_register(struct ptdump_info *info, const char *name)
+{
+	debugfs_create_file(name, 0400, NULL, info, &ptdump_fops);
+}