Adding upstream version 6.1.76.upstream/6.1.76upstream

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

1 files changed, 887 insertions, 0 deletions

diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c
new file mode 100644
index 000000000..27369fa1c
--- /dev/null
+++ b/arch/arm64/kernel/entry-common.c
@@ -0,0 +1,887 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Exception handling code
+ *
+ * Copyright (C) 2019 ARM Ltd.
+ */
+
+#include <linux/context_tracking.h>
+#include <linux/kasan.h>
+#include <linux/linkage.h>
+#include <linux/lockdep.h>
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/thread_info.h>
+
+#include <asm/cpufeature.h>
+#include <asm/daifflags.h>
+#include <asm/esr.h>
+#include <asm/exception.h>
+#include <asm/irq_regs.h>
+#include <asm/kprobes.h>
+#include <asm/mmu.h>
+#include <asm/processor.h>
+#include <asm/sdei.h>
+#include <asm/stacktrace.h>
+#include <asm/sysreg.h>
+#include <asm/system_misc.h>
+
+/*
+ * Handle IRQ/context state management when entering from kernel mode.
+ * Before this function is called it is not safe to call regular kernel code,
+ * intrumentable code, or any code which may trigger an exception.
+ *
+ * This is intended to match the logic in irqentry_enter(), handling the kernel
+ * mode transitions only.
+ */
+static __always_inline void __enter_from_kernel_mode(struct pt_regs *regs)
+{
+	regs->exit_rcu = false;
+
+	if (!IS_ENABLED(CONFIG_TINY_RCU) && is_idle_task(current)) {
+		lockdep_hardirqs_off(CALLER_ADDR0);
+		ct_irq_enter();
+		trace_hardirqs_off_finish();
+
+		regs->exit_rcu = true;
+		return;
+	}
+
+	lockdep_hardirqs_off(CALLER_ADDR0);
+	rcu_irq_enter_check_tick();
+	trace_hardirqs_off_finish();
+}
+
+static void noinstr enter_from_kernel_mode(struct pt_regs *regs)
+{
+	__enter_from_kernel_mode(regs);
+	mte_check_tfsr_entry();
+	mte_disable_tco_entry(current);
+}
+
+/*
+ * Handle IRQ/context state management when exiting to kernel mode.
+ * After this function returns it is not safe to call regular kernel code,
+ * intrumentable code, or any code which may trigger an exception.
+ *
+ * This is intended to match the logic in irqentry_exit(), handling the kernel
+ * mode transitions only, and with preemption handled elsewhere.
+ */
+static __always_inline void __exit_to_kernel_mode(struct pt_regs *regs)
+{
+	lockdep_assert_irqs_disabled();
+
+	if (interrupts_enabled(regs)) {
+		if (regs->exit_rcu) {
+			trace_hardirqs_on_prepare();
+			lockdep_hardirqs_on_prepare();
+			ct_irq_exit();
+			lockdep_hardirqs_on(CALLER_ADDR0);
+			return;
+		}
+
+		trace_hardirqs_on();
+	} else {
+		if (regs->exit_rcu)
+			ct_irq_exit();
+	}
+}
+
+static void noinstr exit_to_kernel_mode(struct pt_regs *regs)
+{
+	mte_check_tfsr_exit();
+	__exit_to_kernel_mode(regs);
+}
+
+/*
+ * Handle IRQ/context state management when entering from user mode.
+ * Before this function is called it is not safe to call regular kernel code,
+ * intrumentable code, or any code which may trigger an exception.
+ */
+static __always_inline void __enter_from_user_mode(void)
+{
+	lockdep_hardirqs_off(CALLER_ADDR0);
+	CT_WARN_ON(ct_state() != CONTEXT_USER);
+	user_exit_irqoff();
+	trace_hardirqs_off_finish();
+	mte_disable_tco_entry(current);
+}
+
+static __always_inline void enter_from_user_mode(struct pt_regs *regs)
+{
+	__enter_from_user_mode();
+}
+
+/*
+ * Handle IRQ/context state management when exiting to user mode.
+ * After this function returns it is not safe to call regular kernel code,
+ * intrumentable code, or any code which may trigger an exception.
+ */
+static __always_inline void __exit_to_user_mode(void)
+{
+	trace_hardirqs_on_prepare();
+	lockdep_hardirqs_on_prepare();
+	user_enter_irqoff();
+	lockdep_hardirqs_on(CALLER_ADDR0);
+}
+
+static __always_inline void prepare_exit_to_user_mode(struct pt_regs *regs)
+{
+	unsigned long flags;
+
+	local_daif_mask();
+
+	flags = read_thread_flags();
+	if (unlikely(flags & _TIF_WORK_MASK))
+		do_notify_resume(regs, flags);
+}
+
+static __always_inline void exit_to_user_mode(struct pt_regs *regs)
+{
+	prepare_exit_to_user_mode(regs);
+	mte_check_tfsr_exit();
+	__exit_to_user_mode();
+}
+
+asmlinkage void noinstr asm_exit_to_user_mode(struct pt_regs *regs)
+{
+	exit_to_user_mode(regs);
+}
+
+/*
+ * Handle IRQ/context state management when entering an NMI from user/kernel
+ * mode. Before this function is called it is not safe to call regular kernel
+ * code, intrumentable code, or any code which may trigger an exception.
+ */
+static void noinstr arm64_enter_nmi(struct pt_regs *regs)
+{
+	regs->lockdep_hardirqs = lockdep_hardirqs_enabled();
+
+	__nmi_enter();
+	lockdep_hardirqs_off(CALLER_ADDR0);
+	lockdep_hardirq_enter();
+	ct_nmi_enter();
+
+	trace_hardirqs_off_finish();
+	ftrace_nmi_enter();
+}
+
+/*
+ * Handle IRQ/context state management when exiting an NMI from user/kernel
+ * mode. After this function returns it is not safe to call regular kernel
+ * code, intrumentable code, or any code which may trigger an exception.
+ */
+static void noinstr arm64_exit_nmi(struct pt_regs *regs)
+{
+	bool restore = regs->lockdep_hardirqs;
+
+	ftrace_nmi_exit();
+	if (restore) {
+		trace_hardirqs_on_prepare();
+		lockdep_hardirqs_on_prepare();
+	}
+
+	ct_nmi_exit();
+	lockdep_hardirq_exit();
+	if (restore)
+		lockdep_hardirqs_on(CALLER_ADDR0);
+	__nmi_exit();
+}
+
+/*
+ * Handle IRQ/context state management when entering a debug exception from
+ * kernel mode. Before this function is called it is not safe to call regular
+ * kernel code, intrumentable code, or any code which may trigger an exception.
+ */
+static void noinstr arm64_enter_el1_dbg(struct pt_regs *regs)
+{
+	regs->lockdep_hardirqs = lockdep_hardirqs_enabled();
+
+	lockdep_hardirqs_off(CALLER_ADDR0);
+	ct_nmi_enter();
+
+	trace_hardirqs_off_finish();
+}
+
+/*
+ * Handle IRQ/context state management when exiting a debug exception from
+ * kernel mode. After this function returns it is not safe to call regular
+ * kernel code, intrumentable code, or any code which may trigger an exception.
+ */
+static void noinstr arm64_exit_el1_dbg(struct pt_regs *regs)
+{
+	bool restore = regs->lockdep_hardirqs;
+
+	if (restore) {
+		trace_hardirqs_on_prepare();
+		lockdep_hardirqs_on_prepare();
+	}
+
+	ct_nmi_exit();
+	if (restore)
+		lockdep_hardirqs_on(CALLER_ADDR0);
+}
+
+#ifdef CONFIG_PREEMPT_DYNAMIC
+DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched);
+#define need_irq_preemption() \
+	(static_branch_unlikely(&sk_dynamic_irqentry_exit_cond_resched))
+#else
+#define need_irq_preemption()	(IS_ENABLED(CONFIG_PREEMPTION))
+#endif
+
+static void __sched arm64_preempt_schedule_irq(void)
+{
+	if (!need_irq_preemption())
+		return;
+
+	/*
+	 * Note: thread_info::preempt_count includes both thread_info::count
+	 * and thread_info::need_resched, and is not equivalent to
+	 * preempt_count().
+	 */
+	if (READ_ONCE(current_thread_info()->preempt_count) != 0)
+		return;
+
+	/*
+	 * DAIF.DA are cleared at the start of IRQ/FIQ handling, and when GIC
+	 * priority masking is used the GIC irqchip driver will clear DAIF.IF
+	 * using gic_arch_enable_irqs() for normal IRQs. If anything is set in
+	 * DAIF we must have handled an NMI, so skip preemption.
+	 */
+	if (system_uses_irq_prio_masking() && read_sysreg(daif))
+		return;
+
+	/*
+	 * Preempting a task from an IRQ means we leave copies of PSTATE
+	 * on the stack. cpufeature's enable calls may modify PSTATE, but
+	 * resuming one of these preempted tasks would undo those changes.
+	 *
+	 * Only allow a task to be preempted once cpufeatures have been
+	 * enabled.
+	 */
+	if (system_capabilities_finalized())
+		preempt_schedule_irq();
+}
+
+static void do_interrupt_handler(struct pt_regs *regs,
+				 void (*handler)(struct pt_regs *))
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	if (on_thread_stack())
+		call_on_irq_stack(regs, handler);
+	else
+		handler(regs);
+
+	set_irq_regs(old_regs);
+}
+
+extern void (*handle_arch_irq)(struct pt_regs *);
+extern void (*handle_arch_fiq)(struct pt_regs *);
+
+static void noinstr __panic_unhandled(struct pt_regs *regs, const char *vector,
+				      unsigned long esr)
+{
+	arm64_enter_nmi(regs);
+
+	console_verbose();
+
+	pr_crit("Unhandled %s exception on CPU%d, ESR 0x%016lx -- %s\n",
+		vector, smp_processor_id(), esr,
+		esr_get_class_string(esr));
+
+	__show_regs(regs);
+	panic("Unhandled exception");
+}
+
+#define UNHANDLED(el, regsize, vector)							\
+asmlinkage void noinstr el##_##regsize##_##vector##_handler(struct pt_regs *regs)	\
+{											\
+	const char *desc = #regsize "-bit " #el " " #vector;				\
+	__panic_unhandled(regs, desc, read_sysreg(esr_el1));				\
+}
+
+#ifdef CONFIG_ARM64_ERRATUM_1463225
+static DEFINE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
+
+static void cortex_a76_erratum_1463225_svc_handler(void)
+{
+	u32 reg, val;
+
+	if (!unlikely(test_thread_flag(TIF_SINGLESTEP)))
+		return;
+
+	if (!unlikely(this_cpu_has_cap(ARM64_WORKAROUND_1463225)))
+		return;
+
+	__this_cpu_write(__in_cortex_a76_erratum_1463225_wa, 1);
+	reg = read_sysreg(mdscr_el1);
+	val = reg | DBG_MDSCR_SS | DBG_MDSCR_KDE;
+	write_sysreg(val, mdscr_el1);
+	asm volatile("msr daifclr, #8");
+	isb();
+
+	/* We will have taken a single-step exception by this point */
+
+	write_sysreg(reg, mdscr_el1);
+	__this_cpu_write(__in_cortex_a76_erratum_1463225_wa, 0);
+}
+
+static __always_inline bool
+cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+{
+	if (!__this_cpu_read(__in_cortex_a76_erratum_1463225_wa))
+		return false;
+
+	/*
+	 * 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 true;
+}
+#else /* CONFIG_ARM64_ERRATUM_1463225 */
+static void cortex_a76_erratum_1463225_svc_handler(void) { }
+static bool cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+{
+	return false;
+}
+#endif /* CONFIG_ARM64_ERRATUM_1463225 */
+
+UNHANDLED(el1t, 64, sync)
+UNHANDLED(el1t, 64, irq)
+UNHANDLED(el1t, 64, fiq)
+UNHANDLED(el1t, 64, error)
+
+static void noinstr el1_abort(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	enter_from_kernel_mode(regs);
+	local_daif_inherit(regs);
+	do_mem_abort(far, esr, regs);
+	local_daif_mask();
+	exit_to_kernel_mode(regs);
+}
+
+static void noinstr el1_pc(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	enter_from_kernel_mode(regs);
+	local_daif_inherit(regs);
+	do_sp_pc_abort(far, esr, regs);
+	local_daif_mask();
+	exit_to_kernel_mode(regs);
+}
+
+static void noinstr el1_undef(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_kernel_mode(regs);
+	local_daif_inherit(regs);
+	do_undefinstr(regs, esr);
+	local_daif_mask();
+	exit_to_kernel_mode(regs);
+}
+
+static void noinstr el1_bti(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_kernel_mode(regs);
+	local_daif_inherit(regs);
+	do_el1_bti(regs, esr);
+	local_daif_mask();
+	exit_to_kernel_mode(regs);
+}
+
+static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	arm64_enter_el1_dbg(regs);
+	if (!cortex_a76_erratum_1463225_debug_handler(regs))
+		do_debug_exception(far, esr, regs);
+	arm64_exit_el1_dbg(regs);
+}
+
+static void noinstr el1_fpac(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_kernel_mode(regs);
+	local_daif_inherit(regs);
+	do_el1_fpac(regs, esr);
+	local_daif_mask();
+	exit_to_kernel_mode(regs);
+}
+
+asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+
+	switch (ESR_ELx_EC(esr)) {
+	case ESR_ELx_EC_DABT_CUR:
+	case ESR_ELx_EC_IABT_CUR:
+		el1_abort(regs, esr);
+		break;
+	/*
+	 * We don't handle ESR_ELx_EC_SP_ALIGN, since we will have hit a
+	 * recursive exception when trying to push the initial pt_regs.
+	 */
+	case ESR_ELx_EC_PC_ALIGN:
+		el1_pc(regs, esr);
+		break;
+	case ESR_ELx_EC_SYS64:
+	case ESR_ELx_EC_UNKNOWN:
+		el1_undef(regs, esr);
+		break;
+	case ESR_ELx_EC_BTI:
+		el1_bti(regs, esr);
+		break;
+	case ESR_ELx_EC_BREAKPT_CUR:
+	case ESR_ELx_EC_SOFTSTP_CUR:
+	case ESR_ELx_EC_WATCHPT_CUR:
+	case ESR_ELx_EC_BRK64:
+		el1_dbg(regs, esr);
+		break;
+	case ESR_ELx_EC_FPAC:
+		el1_fpac(regs, esr);
+		break;
+	default:
+		__panic_unhandled(regs, "64-bit el1h sync", esr);
+	}
+}
+
+static __always_inline void __el1_pnmi(struct pt_regs *regs,
+				       void (*handler)(struct pt_regs *))
+{
+	arm64_enter_nmi(regs);
+	do_interrupt_handler(regs, handler);
+	arm64_exit_nmi(regs);
+}
+
+static __always_inline void __el1_irq(struct pt_regs *regs,
+				      void (*handler)(struct pt_regs *))
+{
+	enter_from_kernel_mode(regs);
+
+	irq_enter_rcu();
+	do_interrupt_handler(regs, handler);
+	irq_exit_rcu();
+
+	arm64_preempt_schedule_irq();
+
+	exit_to_kernel_mode(regs);
+}
+static void noinstr el1_interrupt(struct pt_regs *regs,
+				  void (*handler)(struct pt_regs *))
+{
+	write_sysreg(DAIF_PROCCTX_NOIRQ, daif);
+
+	if (IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) && !interrupts_enabled(regs))
+		__el1_pnmi(regs, handler);
+	else
+		__el1_irq(regs, handler);
+}
+
+asmlinkage void noinstr el1h_64_irq_handler(struct pt_regs *regs)
+{
+	el1_interrupt(regs, handle_arch_irq);
+}
+
+asmlinkage void noinstr el1h_64_fiq_handler(struct pt_regs *regs)
+{
+	el1_interrupt(regs, handle_arch_fiq);
+}
+
+asmlinkage void noinstr el1h_64_error_handler(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+
+	local_daif_restore(DAIF_ERRCTX);
+	arm64_enter_nmi(regs);
+	do_serror(regs, esr);
+	arm64_exit_nmi(regs);
+}
+
+static void noinstr el0_da(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_mem_abort(far, esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_ia(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	/*
+	 * We've taken an instruction abort from userspace and not yet
+	 * re-enabled IRQs. If the address is a kernel address, apply
+	 * BP hardening prior to enabling IRQs and pre-emption.
+	 */
+	if (!is_ttbr0_addr(far))
+		arm64_apply_bp_hardening();
+
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_mem_abort(far, esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_fpsimd_acc(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_sve_acc(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_sve_acc(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_sme_acc(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_sme_acc(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_fpsimd_exc(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_sys(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_sysinstr(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_pc(struct pt_regs *regs, unsigned long esr)
+{
+	unsigned long far = read_sysreg(far_el1);
+
+	if (!is_ttbr0_addr(instruction_pointer(regs)))
+		arm64_apply_bp_hardening();
+
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_sp_pc_abort(far, esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_sp(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_sp_pc_abort(regs->sp, esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_undef(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_undefinstr(regs, esr);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_bti(struct pt_regs *regs)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_el0_bti(regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_inv(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	bad_el0_sync(regs, 0, esr);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_dbg(struct pt_regs *regs, unsigned long esr)
+{
+	/* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */
+	unsigned long far = read_sysreg(far_el1);
+
+	enter_from_user_mode(regs);
+	do_debug_exception(far, esr, regs);
+	local_daif_restore(DAIF_PROCCTX);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_svc(struct pt_regs *regs)
+{
+	enter_from_user_mode(regs);
+	cortex_a76_erratum_1463225_svc_handler();
+	do_el0_svc(regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_fpac(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_el0_fpac(regs, esr);
+	exit_to_user_mode(regs);
+}
+
+asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+
+	switch (ESR_ELx_EC(esr)) {
+	case ESR_ELx_EC_SVC64:
+		el0_svc(regs);
+		break;
+	case ESR_ELx_EC_DABT_LOW:
+		el0_da(regs, esr);
+		break;
+	case ESR_ELx_EC_IABT_LOW:
+		el0_ia(regs, esr);
+		break;
+	case ESR_ELx_EC_FP_ASIMD:
+		el0_fpsimd_acc(regs, esr);
+		break;
+	case ESR_ELx_EC_SVE:
+		el0_sve_acc(regs, esr);
+		break;
+	case ESR_ELx_EC_SME:
+		el0_sme_acc(regs, esr);
+		break;
+	case ESR_ELx_EC_FP_EXC64:
+		el0_fpsimd_exc(regs, esr);
+		break;
+	case ESR_ELx_EC_SYS64:
+	case ESR_ELx_EC_WFx:
+		el0_sys(regs, esr);
+		break;
+	case ESR_ELx_EC_SP_ALIGN:
+		el0_sp(regs, esr);
+		break;
+	case ESR_ELx_EC_PC_ALIGN:
+		el0_pc(regs, esr);
+		break;
+	case ESR_ELx_EC_UNKNOWN:
+		el0_undef(regs, esr);
+		break;
+	case ESR_ELx_EC_BTI:
+		el0_bti(regs);
+		break;
+	case ESR_ELx_EC_BREAKPT_LOW:
+	case ESR_ELx_EC_SOFTSTP_LOW:
+	case ESR_ELx_EC_WATCHPT_LOW:
+	case ESR_ELx_EC_BRK64:
+		el0_dbg(regs, esr);
+		break;
+	case ESR_ELx_EC_FPAC:
+		el0_fpac(regs, esr);
+		break;
+	default:
+		el0_inv(regs, esr);
+	}
+}
+
+static void noinstr el0_interrupt(struct pt_regs *regs,
+				  void (*handler)(struct pt_regs *))
+{
+	enter_from_user_mode(regs);
+
+	write_sysreg(DAIF_PROCCTX_NOIRQ, daif);
+
+	if (regs->pc & BIT(55))
+		arm64_apply_bp_hardening();
+
+	irq_enter_rcu();
+	do_interrupt_handler(regs, handler);
+	irq_exit_rcu();
+
+	exit_to_user_mode(regs);
+}
+
+static void noinstr __el0_irq_handler_common(struct pt_regs *regs)
+{
+	el0_interrupt(regs, handle_arch_irq);
+}
+
+asmlinkage void noinstr el0t_64_irq_handler(struct pt_regs *regs)
+{
+	__el0_irq_handler_common(regs);
+}
+
+static void noinstr __el0_fiq_handler_common(struct pt_regs *regs)
+{
+	el0_interrupt(regs, handle_arch_fiq);
+}
+
+asmlinkage void noinstr el0t_64_fiq_handler(struct pt_regs *regs)
+{
+	__el0_fiq_handler_common(regs);
+}
+
+static void noinstr __el0_error_handler_common(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_ERRCTX);
+	arm64_enter_nmi(regs);
+	do_serror(regs, esr);
+	arm64_exit_nmi(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	exit_to_user_mode(regs);
+}
+
+asmlinkage void noinstr el0t_64_error_handler(struct pt_regs *regs)
+{
+	__el0_error_handler_common(regs);
+}
+
+#ifdef CONFIG_COMPAT
+static void noinstr el0_cp15(struct pt_regs *regs, unsigned long esr)
+{
+	enter_from_user_mode(regs);
+	local_daif_restore(DAIF_PROCCTX);
+	do_cp15instr(esr, regs);
+	exit_to_user_mode(regs);
+}
+
+static void noinstr el0_svc_compat(struct pt_regs *regs)
+{
+	enter_from_user_mode(regs);
+	cortex_a76_erratum_1463225_svc_handler();
+	do_el0_svc_compat(regs);
+	exit_to_user_mode(regs);
+}
+
+asmlinkage void noinstr el0t_32_sync_handler(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+
+	switch (ESR_ELx_EC(esr)) {
+	case ESR_ELx_EC_SVC32:
+		el0_svc_compat(regs);
+		break;
+	case ESR_ELx_EC_DABT_LOW:
+		el0_da(regs, esr);
+		break;
+	case ESR_ELx_EC_IABT_LOW:
+		el0_ia(regs, esr);
+		break;
+	case ESR_ELx_EC_FP_ASIMD:
+		el0_fpsimd_acc(regs, esr);
+		break;
+	case ESR_ELx_EC_FP_EXC32:
+		el0_fpsimd_exc(regs, esr);
+		break;
+	case ESR_ELx_EC_PC_ALIGN:
+		el0_pc(regs, esr);
+		break;
+	case ESR_ELx_EC_UNKNOWN:
+	case ESR_ELx_EC_CP14_MR:
+	case ESR_ELx_EC_CP14_LS:
+	case ESR_ELx_EC_CP14_64:
+		el0_undef(regs, esr);
+		break;
+	case ESR_ELx_EC_CP15_32:
+	case ESR_ELx_EC_CP15_64:
+		el0_cp15(regs, esr);
+		break;
+	case ESR_ELx_EC_BREAKPT_LOW:
+	case ESR_ELx_EC_SOFTSTP_LOW:
+	case ESR_ELx_EC_WATCHPT_LOW:
+	case ESR_ELx_EC_BKPT32:
+		el0_dbg(regs, esr);
+		break;
+	default:
+		el0_inv(regs, esr);
+	}
+}
+
+asmlinkage void noinstr el0t_32_irq_handler(struct pt_regs *regs)
+{
+	__el0_irq_handler_common(regs);
+}
+
+asmlinkage void noinstr el0t_32_fiq_handler(struct pt_regs *regs)
+{
+	__el0_fiq_handler_common(regs);
+}
+
+asmlinkage void noinstr el0t_32_error_handler(struct pt_regs *regs)
+{
+	__el0_error_handler_common(regs);
+}
+#else /* CONFIG_COMPAT */
+UNHANDLED(el0t, 32, sync)
+UNHANDLED(el0t, 32, irq)
+UNHANDLED(el0t, 32, fiq)
+UNHANDLED(el0t, 32, error)
+#endif /* CONFIG_COMPAT */
+
+#ifdef CONFIG_VMAP_STACK
+asmlinkage void noinstr handle_bad_stack(struct pt_regs *regs)
+{
+	unsigned long esr = read_sysreg(esr_el1);
+	unsigned long far = read_sysreg(far_el1);
+
+	arm64_enter_nmi(regs);
+	panic_bad_stack(regs, esr, far);
+}
+#endif /* CONFIG_VMAP_STACK */
+
+#ifdef CONFIG_ARM_SDE_INTERFACE
+asmlinkage noinstr unsigned long
+__sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg)
+{
+	unsigned long ret;
+
+	/*
+	 * We didn't take an exception to get here, so the HW hasn't
+	 * set/cleared bits in PSTATE that we may rely on.
+	 *
+	 * The original SDEI spec (ARM DEN 0054A) can be read ambiguously as to
+	 * whether PSTATE bits are inherited unchanged or generated from
+	 * scratch, and the TF-A implementation always clears PAN and always
+	 * clears UAO. There are no other known implementations.
+	 *
+	 * Subsequent revisions (ARM DEN 0054B) follow the usual rules for how
+	 * PSTATE is modified upon architectural exceptions, and so PAN is
+	 * either inherited or set per SCTLR_ELx.SPAN, and UAO is always
+	 * cleared.
+	 *
+	 * We must explicitly reset PAN to the expected state, including
+	 * clearing it when the host isn't using it, in case a VM had it set.
+	 */
+	if (system_uses_hw_pan())
+		set_pstate_pan(1);
+	else if (cpu_has_pan())
+		set_pstate_pan(0);
+
+	arm64_enter_nmi(regs);
+	ret = do_sdei_event(regs, arg);
+	arm64_exit_nmi(regs);
+
+	return ret;
+}
+#endif /* CONFIG_ARM_SDE_INTERFACE */