mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 16:54:27 +00:00
8245d47cfa
GCC appears to have kind of fragile inlining heuristics, in the sense that it can change whether or not it inlines something based on optimizations. It looks like the kcov instrumentation being added (or in this case, removed) from a function changes the optimization results, and some functions marked "inline" are _not_ inlined. In that case, we end up with __init code calling a function not marked __init, and we get the build warnings I'm trying to eliminate in the coming patch that adds __no_sanitize_coverage to __init functions: WARNING: modpost: vmlinux: section mismatch in reference: xbc_exit+0x8 (section: .text.unlikely) -> _xbc_exit (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: real_mode_size_needed+0x15 (section: .text.unlikely) -> real_mode_blob_end (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: __set_percpu_decrypted+0x16 (section: .text.unlikely) -> early_set_memory_decrypted (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: memblock_alloc_from+0x26 (section: .text.unlikely) -> memblock_alloc_try_nid (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_set_root_pointer+0xc (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_get_root_pointer+0x8 (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: efi_config_table_is_usable+0x16 (section: .text.unlikely) -> xen_efi_config_table_is_usable (section: .init.text) This problem is somewhat fragile (though using either __always_inline or __init will deterministically solve it), but we've tripped over this before with GCC and the solution has usually been to just use __always_inline and move on. For x86 this means forcing several functions to be inline with __always_inline. Link: https://lore.kernel.org/r/20250724055029.3623499-2-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
100 lines
2.1 KiB
C
100 lines
2.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ARCH_X86_REALMODE_H
|
|
#define _ARCH_X86_REALMODE_H
|
|
|
|
/*
|
|
* Flag bit definitions for use with the flags field of the trampoline header
|
|
* in the CONFIG_X86_64 variant.
|
|
*/
|
|
#define TH_FLAGS_SME_ACTIVE_BIT 0
|
|
#define TH_FLAGS_SME_ACTIVE BIT(TH_FLAGS_SME_ACTIVE_BIT)
|
|
|
|
#ifndef __ASSEMBLER__
|
|
|
|
#include <linux/types.h>
|
|
#include <asm/io.h>
|
|
|
|
/* This must match data at realmode/rm/header.S */
|
|
struct real_mode_header {
|
|
u32 text_start;
|
|
u32 ro_end;
|
|
/* SMP trampoline */
|
|
u32 trampoline_start;
|
|
u32 trampoline_header;
|
|
#ifdef CONFIG_AMD_MEM_ENCRYPT
|
|
u32 sev_es_trampoline_start;
|
|
#endif
|
|
#ifdef CONFIG_X86_64
|
|
u32 trampoline_start64;
|
|
u32 trampoline_pgd;
|
|
#endif
|
|
/* ACPI S3 wakeup */
|
|
#ifdef CONFIG_ACPI_SLEEP
|
|
u32 wakeup_start;
|
|
u32 wakeup_header;
|
|
#endif
|
|
/* APM/BIOS reboot */
|
|
u32 machine_real_restart_asm;
|
|
#ifdef CONFIG_X86_64
|
|
u32 machine_real_restart_seg;
|
|
#endif
|
|
};
|
|
|
|
/* This must match data at realmode/rm/trampoline_{32,64}.S */
|
|
struct trampoline_header {
|
|
#ifdef CONFIG_X86_32
|
|
u32 start;
|
|
u16 gdt_pad;
|
|
u16 gdt_limit;
|
|
u32 gdt_base;
|
|
#else
|
|
u64 start;
|
|
u64 efer;
|
|
u32 cr4;
|
|
u32 flags;
|
|
u32 lock;
|
|
#endif
|
|
};
|
|
|
|
extern struct real_mode_header *real_mode_header;
|
|
extern unsigned char real_mode_blob_end[];
|
|
|
|
extern unsigned long initial_code;
|
|
extern unsigned long initial_stack;
|
|
#ifdef CONFIG_AMD_MEM_ENCRYPT
|
|
extern unsigned long initial_vc_handler;
|
|
#endif
|
|
|
|
extern u32 *trampoline_lock;
|
|
|
|
extern unsigned char real_mode_blob[];
|
|
extern unsigned char real_mode_relocs[];
|
|
|
|
#ifdef CONFIG_X86_32
|
|
extern unsigned char startup_32_smp[];
|
|
extern unsigned char boot_gdt[];
|
|
#else
|
|
extern unsigned char secondary_startup_64[];
|
|
extern unsigned char secondary_startup_64_no_verify[];
|
|
#endif
|
|
|
|
static __always_inline size_t real_mode_size_needed(void)
|
|
{
|
|
if (real_mode_header)
|
|
return 0; /* already allocated. */
|
|
|
|
return ALIGN(real_mode_blob_end - real_mode_blob, PAGE_SIZE);
|
|
}
|
|
|
|
static inline void set_real_mode_mem(phys_addr_t mem)
|
|
{
|
|
real_mode_header = (struct real_mode_header *) __va(mem);
|
|
}
|
|
|
|
void reserve_real_mode(void);
|
|
void load_trampoline_pgtable(void);
|
|
void init_real_mode(void);
|
|
|
|
#endif /* __ASSEMBLER__ */
|
|
|
|
#endif /* _ARCH_X86_REALMODE_H */
|