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-rw-r--r--arch/x86/kernel/vmlinux.lds.S539
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diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
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--- /dev/null
+++ b/arch/x86/kernel/vmlinux.lds.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ld script for the x86 kernel
+ *
+ * Historic 32-bit version written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ *
+ * Modernisation, unification and other changes and fixes:
+ * Copyright (C) 2007-2009 Sam Ravnborg <sam@ravnborg.org>
+ *
+ *
+ * Don't define absolute symbols until and unless you know that symbol
+ * value is should remain constant even if kernel image is relocated
+ * at run time. Absolute symbols are not relocated. If symbol value should
+ * change if kernel is relocated, make the symbol section relative and
+ * put it inside the section definition.
+ */
+
+#ifdef CONFIG_X86_32
+#define LOAD_OFFSET __PAGE_OFFSET
+#else
+#define LOAD_OFFSET __START_KERNEL_map
+#endif
+
+#define RUNTIME_DISCARD_EXIT
+#define EMITS_PT_NOTE
+#define RO_EXCEPTION_TABLE_ALIGN 16
+
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/page_types.h>
+#include <asm/orc_lookup.h>
+#include <asm/cache.h>
+#include <asm/boot.h>
+
+#undef i386 /* in case the preprocessor is a 32bit one */
+
+OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT)
+
+#ifdef CONFIG_X86_32
+OUTPUT_ARCH(i386)
+ENTRY(phys_startup_32)
+#else
+OUTPUT_ARCH(i386:x86-64)
+ENTRY(phys_startup_64)
+#endif
+
+jiffies = jiffies_64;
+
+#if defined(CONFIG_X86_64)
+/*
+ * On 64-bit, align RODATA to 2MB so we retain large page mappings for
+ * boundaries spanning kernel text, rodata and data sections.
+ *
+ * However, kernel identity mappings will have different RWX permissions
+ * to the pages mapping to text and to the pages padding (which are freed) the
+ * text section. Hence kernel identity mappings will be broken to smaller
+ * pages. For 64-bit, kernel text and kernel identity mappings are different,
+ * so we can enable protection checks as well as retain 2MB large page
+ * mappings for kernel text.
+ */
+#define X86_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
+
+#define X86_ALIGN_RODATA_END \
+ . = ALIGN(HPAGE_SIZE); \
+ __end_rodata_hpage_align = .; \
+ __end_rodata_aligned = .;
+
+#define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE);
+#define ALIGN_ENTRY_TEXT_END . = ALIGN(PMD_SIZE);
+
+/*
+ * This section contains data which will be mapped as decrypted. Memory
+ * encryption operates on a page basis. Make this section PMD-aligned
+ * to avoid splitting the pages while mapping the section early.
+ *
+ * Note: We use a separate section so that only this section gets
+ * decrypted to avoid exposing more than we wish.
+ */
+#define BSS_DECRYPTED \
+ . = ALIGN(PMD_SIZE); \
+ __start_bss_decrypted = .; \
+ *(.bss..decrypted); \
+ . = ALIGN(PAGE_SIZE); \
+ __start_bss_decrypted_unused = .; \
+ . = ALIGN(PMD_SIZE); \
+ __end_bss_decrypted = .; \
+
+#else
+
+#define X86_ALIGN_RODATA_BEGIN
+#define X86_ALIGN_RODATA_END \
+ . = ALIGN(PAGE_SIZE); \
+ __end_rodata_aligned = .;
+
+#define ALIGN_ENTRY_TEXT_BEGIN
+#define ALIGN_ENTRY_TEXT_END
+#define BSS_DECRYPTED
+
+#endif
+
+PHDRS {
+ text PT_LOAD FLAGS(5); /* R_E */
+ data PT_LOAD FLAGS(6); /* RW_ */
+#ifdef CONFIG_X86_64
+#ifdef CONFIG_SMP
+ percpu PT_LOAD FLAGS(6); /* RW_ */
+#endif
+ init PT_LOAD FLAGS(7); /* RWE */
+#endif
+ note PT_NOTE FLAGS(0); /* ___ */
+}
+
+SECTIONS
+{
+#ifdef CONFIG_X86_32
+ . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
+ phys_startup_32 = ABSOLUTE(startup_32 - LOAD_OFFSET);
+#else
+ . = __START_KERNEL;
+ phys_startup_64 = ABSOLUTE(startup_64 - LOAD_OFFSET);
+#endif
+
+ /* Text and read-only data */
+ .text : AT(ADDR(.text) - LOAD_OFFSET) {
+ _text = .;
+ _stext = .;
+ /* bootstrapping code */
+ HEAD_TEXT
+ TEXT_TEXT
+ SCHED_TEXT
+ CPUIDLE_TEXT
+ LOCK_TEXT
+ KPROBES_TEXT
+ ALIGN_ENTRY_TEXT_BEGIN
+#ifdef CONFIG_CPU_SRSO
+ *(.text..__x86.rethunk_untrain)
+#endif
+
+ ENTRY_TEXT
+
+#ifdef CONFIG_CPU_SRSO
+ /*
+ * See the comment above srso_alias_untrain_ret()'s
+ * definition.
+ */
+ . = srso_alias_untrain_ret | (1 << 2) | (1 << 8) | (1 << 14) | (1 << 20);
+ *(.text..__x86.rethunk_safe)
+#endif
+ ALIGN_ENTRY_TEXT_END
+ SOFTIRQENTRY_TEXT
+ STATIC_CALL_TEXT
+ *(.gnu.warning)
+
+#ifdef CONFIG_RETPOLINE
+ __indirect_thunk_start = .;
+ *(.text..__x86.indirect_thunk)
+ *(.text..__x86.return_thunk)
+ __indirect_thunk_end = .;
+#endif
+ } :text =0xcccc
+
+ /* End of text section, which should occupy whole number of pages */
+ _etext = .;
+
+ . = ALIGN(PAGE_SIZE);
+
+ X86_ALIGN_RODATA_BEGIN
+ RO_DATA(PAGE_SIZE)
+ X86_ALIGN_RODATA_END
+
+ /* Data */
+ .data : AT(ADDR(.data) - LOAD_OFFSET) {
+ /* Start of data section */
+ _sdata = .;
+
+ /* init_task */
+ INIT_TASK_DATA(THREAD_SIZE)
+
+#ifdef CONFIG_X86_32
+ /* 32 bit has nosave before _edata */
+ NOSAVE_DATA
+#endif
+
+ PAGE_ALIGNED_DATA(PAGE_SIZE)
+
+ CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)
+
+ DATA_DATA
+ CONSTRUCTORS
+
+ /* rarely changed data like cpu maps */
+ READ_MOSTLY_DATA(INTERNODE_CACHE_BYTES)
+
+ /* End of data section */
+ _edata = .;
+ } :data
+
+ BUG_TABLE
+
+ ORC_UNWIND_TABLE
+
+ . = ALIGN(PAGE_SIZE);
+ __vvar_page = .;
+
+ .vvar : AT(ADDR(.vvar) - LOAD_OFFSET) {
+ /* work around gold bug 13023 */
+ __vvar_beginning_hack = .;
+
+ /* Place all vvars at the offsets in asm/vvar.h. */
+#define EMIT_VVAR(name, offset) \
+ . = __vvar_beginning_hack + offset; \
+ *(.vvar_ ## name)
+#include <asm/vvar.h>
+#undef EMIT_VVAR
+
+ /*
+ * Pad the rest of the page with zeros. Otherwise the loader
+ * can leave garbage here.
+ */
+ . = __vvar_beginning_hack + PAGE_SIZE;
+ } :data
+
+ . = ALIGN(__vvar_page + PAGE_SIZE, PAGE_SIZE);
+
+ /* Init code and data - will be freed after init */
+ . = ALIGN(PAGE_SIZE);
+ .init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) {
+ __init_begin = .; /* paired with __init_end */
+ }
+
+#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
+ /*
+ * percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the
+ * output PHDR, so the next output section - .init.text - should
+ * start another segment - init.
+ */
+ PERCPU_VADDR(INTERNODE_CACHE_BYTES, 0, :percpu)
+ ASSERT(SIZEOF(.data..percpu) < CONFIG_PHYSICAL_START,
+ "per-CPU data too large - increase CONFIG_PHYSICAL_START")
+#endif
+
+ INIT_TEXT_SECTION(PAGE_SIZE)
+#ifdef CONFIG_X86_64
+ :init
+#endif
+
+ /*
+ * Section for code used exclusively before alternatives are run. All
+ * references to such code must be patched out by alternatives, normally
+ * by using X86_FEATURE_ALWAYS CPU feature bit.
+ *
+ * See static_cpu_has() for an example.
+ */
+ .altinstr_aux : AT(ADDR(.altinstr_aux) - LOAD_OFFSET) {
+ *(.altinstr_aux)
+ }
+
+ INIT_DATA_SECTION(16)
+
+ .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
+ __x86_cpu_dev_start = .;
+ *(.x86_cpu_dev.init)
+ __x86_cpu_dev_end = .;
+ }
+
+#ifdef CONFIG_X86_INTEL_MID
+ .x86_intel_mid_dev.init : AT(ADDR(.x86_intel_mid_dev.init) - \
+ LOAD_OFFSET) {
+ __x86_intel_mid_dev_start = .;
+ *(.x86_intel_mid_dev.init)
+ __x86_intel_mid_dev_end = .;
+ }
+#endif
+
+ /*
+ * start address and size of operations which during runtime
+ * can be patched with virtualization friendly instructions or
+ * baremetal native ones. Think page table operations.
+ * Details in paravirt_types.h
+ */
+ . = ALIGN(8);
+ .parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
+ __parainstructions = .;
+ *(.parainstructions)
+ __parainstructions_end = .;
+ }
+
+#ifdef CONFIG_RETPOLINE
+ /*
+ * List of instructions that call/jmp/jcc to retpoline thunks
+ * __x86_indirect_thunk_*(). These instructions can be patched along
+ * with alternatives, after which the section can be freed.
+ */
+ . = ALIGN(8);
+ .retpoline_sites : AT(ADDR(.retpoline_sites) - LOAD_OFFSET) {
+ __retpoline_sites = .;
+ *(.retpoline_sites)
+ __retpoline_sites_end = .;
+ }
+
+ . = ALIGN(8);
+ .return_sites : AT(ADDR(.return_sites) - LOAD_OFFSET) {
+ __return_sites = .;
+ *(.return_sites)
+ __return_sites_end = .;
+ }
+#endif
+
+#ifdef CONFIG_X86_KERNEL_IBT
+ . = ALIGN(8);
+ .ibt_endbr_seal : AT(ADDR(.ibt_endbr_seal) - LOAD_OFFSET) {
+ __ibt_endbr_seal = .;
+ *(.ibt_endbr_seal)
+ __ibt_endbr_seal_end = .;
+ }
+#endif
+
+ /*
+ * struct alt_inst entries. From the header (alternative.h):
+ * "Alternative instructions for different CPU types or capabilities"
+ * Think locking instructions on spinlocks.
+ */
+ . = ALIGN(8);
+ .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
+ __alt_instructions = .;
+ *(.altinstructions)
+ __alt_instructions_end = .;
+ }
+
+ /*
+ * And here are the replacement instructions. The linker sticks
+ * them as binary blobs. The .altinstructions has enough data to
+ * get the address and the length of them to patch the kernel safely.
+ */
+ .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
+ *(.altinstr_replacement)
+ }
+
+ . = ALIGN(8);
+ .apicdrivers : AT(ADDR(.apicdrivers) - LOAD_OFFSET) {
+ __apicdrivers = .;
+ *(.apicdrivers);
+ __apicdrivers_end = .;
+ }
+
+ . = ALIGN(8);
+ /*
+ * .exit.text is discarded at runtime, not link time, to deal with
+ * references from .altinstructions
+ */
+ .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
+ EXIT_TEXT
+ }
+
+ .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
+ EXIT_DATA
+ }
+
+#if !defined(CONFIG_X86_64) || !defined(CONFIG_SMP)
+ PERCPU_SECTION(INTERNODE_CACHE_BYTES)
+#endif
+
+ . = ALIGN(PAGE_SIZE);
+
+ /* freed after init ends here */
+ .init.end : AT(ADDR(.init.end) - LOAD_OFFSET) {
+ __init_end = .;
+ }
+
+ /*
+ * smp_locks might be freed after init
+ * start/end must be page aligned
+ */
+ . = ALIGN(PAGE_SIZE);
+ .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
+ __smp_locks = .;
+ *(.smp_locks)
+ . = ALIGN(PAGE_SIZE);
+ __smp_locks_end = .;
+ }
+
+#ifdef CONFIG_X86_64
+ .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
+ NOSAVE_DATA
+ }
+#endif
+
+ /* BSS */
+ . = ALIGN(PAGE_SIZE);
+ .bss : AT(ADDR(.bss) - LOAD_OFFSET) {
+ __bss_start = .;
+ *(.bss..page_aligned)
+ . = ALIGN(PAGE_SIZE);
+ *(BSS_MAIN)
+ BSS_DECRYPTED
+ . = ALIGN(PAGE_SIZE);
+ __bss_stop = .;
+ }
+
+ /*
+ * The memory occupied from _text to here, __end_of_kernel_reserve, is
+ * automatically reserved in setup_arch(). Anything after here must be
+ * explicitly reserved using memblock_reserve() or it will be discarded
+ * and treated as available memory.
+ */
+ __end_of_kernel_reserve = .;
+
+ . = ALIGN(PAGE_SIZE);
+ .brk : AT(ADDR(.brk) - LOAD_OFFSET) {
+ __brk_base = .;
+ . += 64 * 1024; /* 64k alignment slop space */
+ *(.bss..brk) /* areas brk users have reserved */
+ __brk_limit = .;
+ }
+
+ . = ALIGN(PAGE_SIZE); /* keep VO_INIT_SIZE page aligned */
+ _end = .;
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ /*
+ * Early scratch/workarea section: Lives outside of the kernel proper
+ * (_text - _end).
+ *
+ * Resides after _end because even though the .brk section is after
+ * __end_of_kernel_reserve, the .brk section is later reserved as a
+ * part of the kernel. Since it is located after __end_of_kernel_reserve
+ * it will be discarded and become part of the available memory. As
+ * such, it can only be used by very early boot code and must not be
+ * needed afterwards.
+ *
+ * Currently used by SME for performing in-place encryption of the
+ * kernel during boot. Resides on a 2MB boundary to simplify the
+ * pagetable setup used for SME in-place encryption.
+ */
+ . = ALIGN(HPAGE_SIZE);
+ .init.scratch : AT(ADDR(.init.scratch) - LOAD_OFFSET) {
+ __init_scratch_begin = .;
+ *(.init.scratch)
+ . = ALIGN(HPAGE_SIZE);
+ __init_scratch_end = .;
+ }
+#endif
+
+ STABS_DEBUG
+ DWARF_DEBUG
+ ELF_DETAILS
+
+ DISCARDS
+
+ /*
+ * Make sure that the .got.plt is either completely empty or it
+ * contains only the lazy dispatch entries.
+ */
+ .got.plt (INFO) : { *(.got.plt) }
+ ASSERT(SIZEOF(.got.plt) == 0 ||
+#ifdef CONFIG_X86_64
+ SIZEOF(.got.plt) == 0x18,
+#else
+ SIZEOF(.got.plt) == 0xc,
+#endif
+ "Unexpected GOT/PLT entries detected!")
+
+ /*
+ * Sections that should stay zero sized, which is safer to
+ * explicitly check instead of blindly discarding.
+ */
+ .got : {
+ *(.got) *(.igot.*)
+ }
+ ASSERT(SIZEOF(.got) == 0, "Unexpected GOT entries detected!")
+
+ .plt : {
+ *(.plt) *(.plt.*) *(.iplt)
+ }
+ ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages detected!")
+
+ .rel.dyn : {
+ *(.rel.*) *(.rel_*)
+ }
+ ASSERT(SIZEOF(.rel.dyn) == 0, "Unexpected run-time relocations (.rel) detected!")
+
+ .rela.dyn : {
+ *(.rela.*) *(.rela_*)
+ }
+ ASSERT(SIZEOF(.rela.dyn) == 0, "Unexpected run-time relocations (.rela) detected!")
+}
+
+/*
+ * The ASSERT() sink to . is intentional, for binutils 2.14 compatibility:
+ */
+. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
+ "kernel image bigger than KERNEL_IMAGE_SIZE");
+
+#ifdef CONFIG_X86_64
+/*
+ * Per-cpu symbols which need to be offset from __per_cpu_load
+ * for the boot processor.
+ */
+#define INIT_PER_CPU(x) init_per_cpu__##x = ABSOLUTE(x) + __per_cpu_load
+INIT_PER_CPU(gdt_page);
+INIT_PER_CPU(fixed_percpu_data);
+INIT_PER_CPU(irq_stack_backing_store);
+
+#ifdef CONFIG_SMP
+. = ASSERT((fixed_percpu_data == 0),
+ "fixed_percpu_data is not at start of per-cpu area");
+#endif
+
+#ifdef CONFIG_RETHUNK
+. = ASSERT((retbleed_return_thunk & 0x3f) == 0, "retbleed_return_thunk not cacheline-aligned");
+. = ASSERT((srso_safe_ret & 0x3f) == 0, "srso_safe_ret not cacheline-aligned");
+#endif
+
+#ifdef CONFIG_CPU_SRSO
+/*
+ * GNU ld cannot do XOR until 2.41.
+ * https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=f6f78318fca803c4907fb8d7f6ded8295f1947b1
+ *
+ * LLVM lld cannot do XOR until lld-17.
+ * https://github.com/llvm/llvm-project/commit/fae96104d4378166cbe5c875ef8ed808a356f3fb
+ *
+ * Instead do: (A | B) - (A & B) in order to compute the XOR
+ * of the two function addresses:
+ */
+. = ASSERT(((ABSOLUTE(srso_alias_untrain_ret) | srso_alias_safe_ret) -
+ (ABSOLUTE(srso_alias_untrain_ret) & srso_alias_safe_ret)) == ((1 << 2) | (1 << 8) | (1 << 14) | (1 << 20)),
+ "SRSO function pair won't alias");
+#endif
+
+#endif /* CONFIG_X86_64 */
+
+#ifdef CONFIG_KEXEC_CORE
+#include <asm/kexec.h>
+
+. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
+ "kexec control code size is too big");
+#endif
+