/* 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.
 */

#define LOAD_OFFSET __START_KERNEL_map

#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>
#include <asm/kexec.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;
const_current_task = current_task;
const_cpu_current_top_of_stack = cpu_current_top_of_stack;

#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);
#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
#endif

#ifdef CONFIG_AMD_MEM_ENCRYPT
/*
 * 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 = .;                              \
        __pi___start_bss_decrypted = .;                         \
        *(.bss..decrypted);                                     \
        . = ALIGN(PAGE_SIZE);                                   \
        __start_bss_decrypted_unused = .;                       \
        . = ALIGN(PMD_SIZE);                                    \
        __end_bss_decrypted = .;                                \
        __pi___end_bss_decrypted = .;                           \

#else
#define BSS_DECRYPTED
#endif

#if defined(CONFIG_X86_64) && defined(CONFIG_KEXEC_CORE)
#define KEXEC_RELOCATE_KERNEL                                   \
        . = ALIGN(0x100);                                       \
        __relocate_kernel_start = .;                            \
        *(.text..relocate_kernel);                              \
        *(.data..relocate_kernel);                              \
        __relocate_kernel_end = .;

ASSERT(__relocate_kernel_end - __relocate_kernel_start <= KEXEC_CONTROL_CODE_MAX_SIZE,
        "relocate_kernel code too large!")
#else
#define KEXEC_RELOCATE_KERNEL
#endif
PHDRS {
        text PT_LOAD FLAGS(5);          /* R_E */
        data PT_LOAD FLAGS(6);          /* RW_ */
        note PT_NOTE FLAGS(0);          /* ___ */
}

SECTIONS
{
        . = __START_KERNEL;
#ifdef CONFIG_X86_32
        phys_startup_32 = ABSOLUTE(startup_32 - LOAD_OFFSET);
#else
        phys_startup_64 = ABSOLUTE(startup_64 - LOAD_OFFSET);
#endif

        /* Text and read-only data */
        .text :  AT(ADDR(.text) - LOAD_OFFSET) {
                _text = .;
                __pi__text = .;
                _stext = .;
                ALIGN_ENTRY_TEXT_BEGIN
                *(.text..__x86.rethunk_untrain)
                ENTRY_TEXT

#ifdef CONFIG_MITIGATION_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

                TEXT_TEXT
                SCHED_TEXT
                LOCK_TEXT
                KPROBES_TEXT
                SOFTIRQENTRY_TEXT
#ifdef CONFIG_MITIGATION_RETPOLINE
                *(.text..__x86.indirect_thunk)
                *(.text..__x86.return_thunk)
#endif
                STATIC_CALL_TEXT
                *(.gnu.warning)

        } :text = 0xcccccccc

        /* 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)

                /* equivalent to task_pt_regs(&init_task) */
                __top_init_kernel_stack = __end_init_stack - TOP_OF_KERNEL_STACK_PADDING - PTREGS_SIZE;

#ifdef CONFIG_X86_32
                /* 32 bit has nosave before _edata */
                NOSAVE_DATA
#endif

                PAGE_ALIGNED_DATA(PAGE_SIZE)

                CACHE_HOT_DATA(L1_CACHE_BYTES)

                CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)

                DATA_DATA
                CONSTRUCTORS
                KEXEC_RELOCATE_KERNEL

                /* rarely changed data like cpu maps */
                READ_MOSTLY_DATA(INTERNODE_CACHE_BYTES)

                /* End of data section */
                _edata = .;
        } :data

        BUG_TABLE

        ORC_UNWIND_TABLE

        /* 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 */
        }

        INIT_TEXT_SECTION(PAGE_SIZE)

        /*
         * 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)
                . = ALIGN(PAGE_SIZE);
                __inittext_end = .;
        }

        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

#ifdef CONFIG_MITIGATION_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 = .;
        }

        . = ALIGN(8);
        .call_sites : AT(ADDR(.call_sites) - LOAD_OFFSET) {
                __call_sites = .;
                *(.call_sites)
                __call_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

#ifdef CONFIG_FINEIBT
        . = ALIGN(8);
        .cfi_sites : AT(ADDR(.cfi_sites) - LOAD_OFFSET) {
                __cfi_sites = .;
                *(.cfi_sites)
                __cfi_sites_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
        }

        PERCPU_SECTION(L1_CACHE_BYTES)
        ASSERT(__per_cpu_hot_end - __per_cpu_hot_start <= 64, "percpu cache hot data too large")

        RUNTIME_CONST_VARIABLES
        RUNTIME_CONST(ptr, USER_PTR_MAX)

        . = 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 = .;
        __pi__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
#ifdef CONFIG_PROPELLER_CLANG
        .llvm_bb_addr_map : { *(.llvm_bb_addr_map) }
#endif

        MODINFO
        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!")
}

/*
 * COMPILE_TEST kernels can be large - CONFIG_KASAN, for example, can cause
 * this.  Let's assume that nobody will be running a COMPILE_TEST kernel and
 * let's assert that fuller build coverage is more valuable than being able to
 * run a COMPILE_TEST kernel.
 */
#ifndef CONFIG_COMPILE_TEST
/*
 * The ASSERT() sync to . is intentional, for binutils 2.14 compatibility:
 */
. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
           "kernel image bigger than KERNEL_IMAGE_SIZE");
#endif

/* needed for Clang - see arch/x86/entry/entry.S */
PROVIDE(__ref_stack_chk_guard = __stack_chk_guard);

#ifdef CONFIG_X86_64

#ifdef CONFIG_MITIGATION_UNRET_ENTRY
. = ASSERT((retbleed_return_thunk & 0x3f) == 0, "retbleed_return_thunk not cacheline-aligned");
#endif

#ifdef CONFIG_MITIGATION_SRSO
. = ASSERT((srso_safe_ret & 0x3f) == 0, "srso_safe_ret not cacheline-aligned");
/*
 * 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

#if defined(CONFIG_MITIGATION_ITS) && !defined(CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B)
. = ASSERT(__x86_indirect_its_thunk_rax & 0x20, "__x86_indirect_thunk_rax not in second half of cacheline");
. = ASSERT(((__x86_indirect_its_thunk_rcx - __x86_indirect_its_thunk_rax) % 64) == 0, "Indirect thunks are not cacheline apart");
. = ASSERT(__x86_indirect_its_thunk_array == __x86_indirect_its_thunk_rax, "Gap in ITS thunk array");
#endif

#if defined(CONFIG_MITIGATION_ITS) && !defined(CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B)
. = ASSERT(its_return_thunk & 0x20, "its_return_thunk not in second half of cacheline");
#endif

#endif /* CONFIG_X86_64 */

/*
 * The symbols below are referenced using relative relocations in the
 * respective ELF notes. This produces build time constants that the
 * linker will never mark as relocatable. (Using just ABSOLUTE() is not
 * sufficient for that).
 */
#ifdef CONFIG_XEN_PV
xen_elfnote_entry_value =
        ABSOLUTE(xen_elfnote_entry) + ABSOLUTE(startup_xen);
#endif
#ifdef CONFIG_PVH
xen_elfnote_phys32_entry_value =
        ABSOLUTE(xen_elfnote_phys32_entry) + ABSOLUTE(pvh_start_xen - LOAD_OFFSET);
#endif

#include "../boot/startup/exports.h"