diff options
Diffstat (limited to 'arch/x86/include/asm/alternative.h')
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 65f79092c9d9..fcd20c6dc7f9 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -10,6 +10,9 @@ #define ALT_FLAG_NOT (1 << 0) #define ALT_NOT(feature) ((ALT_FLAG_NOT << ALT_FLAGS_SHIFT) | (feature)) +#define ALT_FLAG_DIRECT_CALL (1 << 1) +#define ALT_DIRECT_CALL(feature) ((ALT_FLAG_DIRECT_CALL << ALT_FLAGS_SHIFT) | (feature)) +#define ALT_CALL_ALWAYS ALT_DIRECT_CALL(X86_FEATURE_ALWAYS) #ifndef __ASSEMBLY__ @@ -86,6 +89,8 @@ struct alt_instr { u8 replacementlen; /* length of new instruction */ } __packed; +extern struct alt_instr __alt_instructions[], __alt_instructions_end[]; + /* * Debug flag that can be tested to see whether alternative * instructions were patched in already: @@ -101,11 +106,10 @@ extern void apply_fineibt(s32 *start_retpoline, s32 *end_retpoine, s32 *start_cfi, s32 *end_cfi); struct module; -struct paravirt_patch_site; struct callthunk_sites { s32 *call_start, *call_end; - struct paravirt_patch_site *pv_start, *pv_end; + struct alt_instr *alt_start, *alt_end; }; #ifdef CONFIG_CALL_THUNKS @@ -150,6 +154,8 @@ static inline int alternatives_text_reserved(void *start, void *end) } #endif /* CONFIG_SMP */ +#define ALT_CALL_INSTR "call BUG_func" + #define b_replacement(num) "664"#num #define e_replacement(num) "665"#num @@ -330,6 +336,22 @@ static inline int alternatives_text_reserved(void *start, void *end) */ #define ASM_NO_INPUT_CLOBBER(clbr...) "i" (0) : clbr +/* Macro for creating assembler functions avoiding any C magic. */ +#define DEFINE_ASM_FUNC(func, instr, sec) \ + asm (".pushsection " #sec ", \"ax\"\n" \ + ".global " #func "\n\t" \ + ".type " #func ", @function\n\t" \ + ASM_FUNC_ALIGN "\n" \ + #func ":\n\t" \ + ASM_ENDBR \ + instr "\n\t" \ + ASM_RET \ + ".size " #func ", . - " #func "\n\t" \ + ".popsection") + +void BUG_func(void); +void nop_func(void); + #else /* __ASSEMBLY__ */ #ifdef CONFIG_SMP @@ -370,6 +392,10 @@ static inline int alternatives_text_reserved(void *start, void *end) .byte \alt_len .endm +.macro ALT_CALL_INSTR + call BUG_func +.endm + /* * Define an alternative between two instructions. If @feature is * present, early code in apply_alternatives() replaces @oldinstr with |