diff options
Diffstat (limited to 'arch/x86/include/asm/alternative.h')
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 101 |
1 files changed, 52 insertions, 49 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index dc03a647776d..f2294784babc 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -4,7 +4,9 @@ #include <linux/types.h> #include <linux/stringify.h> +#include <linux/objtool.h> #include <asm/asm.h> +#include <asm/bug.h> #define ALT_FLAGS_SHIFT 16 @@ -14,7 +16,7 @@ #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__ +#ifndef __ASSEMBLER__ #include <linux/stddef.h> @@ -47,7 +49,7 @@ ".popsection\n" \ "671:" -#define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock; " +#define LOCK_PREFIX LOCK_PREFIX_HERE "\n\tlock " #else /* ! CONFIG_SMP */ #define LOCK_PREFIX_HERE "" @@ -55,16 +57,6 @@ #endif /* - * objtool annotation to ignore the alternatives and only consider the original - * instruction(s). - */ -#define ANNOTATE_IGNORE_ALTERNATIVE \ - "999:\n\t" \ - ".pushsection .discard.ignore_alts\n\t" \ - ".long 999b\n\t" \ - ".popsection\n\t" - -/* * The patching flags are part of the upper bits of the @ft_flags parameter when * specifying them. The split is currently like this: * @@ -96,20 +88,19 @@ extern struct alt_instr __alt_instructions[], __alt_instructions_end[]; * instructions were patched in already: */ extern int alternatives_patched; -struct module; extern void alternative_instructions(void); -extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end, - struct module *mod); -extern void apply_retpolines(s32 *start, s32 *end, struct module *mod); -extern void apply_returns(s32 *start, s32 *end, struct module *mod); -extern void apply_seal_endbr(s32 *start, s32 *end, struct module *mod); +extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end); +extern void apply_retpolines(s32 *start, s32 *end); +extern void apply_returns(s32 *start, s32 *end); +extern void apply_seal_endbr(s32 *start, s32 *end); extern void apply_fineibt(s32 *start_retpoline, s32 *end_retpoine, - s32 *start_cfi, s32 *end_cfi, struct module *mod); + s32 *start_cfi, s32 *end_cfi); + +struct module; struct callthunk_sites { s32 *call_start, *call_end; - struct alt_instr *alt_start, *alt_end; }; #ifdef CONFIG_CALL_THUNKS @@ -134,6 +125,37 @@ static __always_inline int x86_call_depth_emit_accounting(u8 **pprog, } #endif +#ifdef CONFIG_MITIGATION_ITS +extern void its_init_mod(struct module *mod); +extern void its_fini_mod(struct module *mod); +extern void its_free_mod(struct module *mod); +extern u8 *its_static_thunk(int reg); +#else /* CONFIG_MITIGATION_ITS */ +static inline void its_init_mod(struct module *mod) { } +static inline void its_fini_mod(struct module *mod) { } +static inline void its_free_mod(struct module *mod) { } +static inline u8 *its_static_thunk(int reg) +{ + WARN_ONCE(1, "ITS not compiled in"); + + return NULL; +} +#endif + +#if defined(CONFIG_MITIGATION_RETHUNK) && defined(CONFIG_OBJTOOL) +extern bool cpu_wants_rethunk(void); +extern bool cpu_wants_rethunk_at(void *addr); +#else +static __always_inline bool cpu_wants_rethunk(void) +{ + return false; +} +static __always_inline bool cpu_wants_rethunk_at(void *addr) +{ + return false; +} +#endif + #ifdef CONFIG_SMP extern void alternatives_smp_module_add(struct module *mod, char *name, void *locks, void *locks_end, @@ -246,10 +268,12 @@ static inline int alternatives_text_reserved(void *start, void *end) * references: i.e., if used for a function, it would add the PLT * suffix. */ -#define alternative_call(oldfunc, newfunc, ft_flags, output, input...) \ +#define alternative_call(oldfunc, newfunc, ft_flags, output, input, clobbers...) \ asm_inline volatile(ALTERNATIVE("call %c[old]", "call %c[new]", ft_flags) \ : ALT_OUTPUT_SP(output) \ - : [old] "i" (oldfunc), [new] "i" (newfunc), ## input) + : [old] "i" (oldfunc), [new] "i" (newfunc) \ + COMMA(input) \ + : clobbers) /* * Like alternative_call, but there are two features and respective functions. @@ -258,24 +282,14 @@ static inline int alternatives_text_reserved(void *start, void *end) * Otherwise, old function is used. */ #define alternative_call_2(oldfunc, newfunc1, ft_flags1, newfunc2, ft_flags2, \ - output, input...) \ + output, input, clobbers...) \ asm_inline volatile(ALTERNATIVE_2("call %c[old]", "call %c[new1]", ft_flags1, \ "call %c[new2]", ft_flags2) \ : ALT_OUTPUT_SP(output) \ : [old] "i" (oldfunc), [new1] "i" (newfunc1), \ - [new2] "i" (newfunc2), ## input) - -/* - * use this macro(s) if you need more than one output parameter - * in alternative_io - */ -#define ASM_OUTPUT2(a...) a - -/* - * use this macro if you need clobbers but no inputs in - * alternative_{input,io,call}() - */ -#define ASM_NO_INPUT_CLOBBER(clbr...) "i" (0) : clbr + [new2] "i" (newfunc2) \ + COMMA(input) \ + : clobbers) #define ALT_OUTPUT_SP(...) ASM_CALL_CONSTRAINT, ## __VA_ARGS__ @@ -295,7 +309,7 @@ static inline int alternatives_text_reserved(void *start, void *end) void BUG_func(void); void nop_func(void); -#else /* __ASSEMBLY__ */ +#else /* __ASSEMBLER__ */ #ifdef CONFIG_SMP .macro LOCK_PREFIX @@ -311,17 +325,6 @@ void nop_func(void); #endif /* - * objtool annotation to ignore the alternatives and only consider the original - * instruction(s). - */ -.macro ANNOTATE_IGNORE_ALTERNATIVE - .Lannotate_\@: - .pushsection .discard.ignore_alts - .long .Lannotate_\@ - .popsection -.endm - -/* * Issue one struct alt_instr descriptor entry (need to put it into * the section .altinstructions, see below). This entry contains * enough information for the alternatives patching code to patch an @@ -389,6 +392,6 @@ void nop_func(void); ALTERNATIVE_2 oldinstr, newinstr_no, X86_FEATURE_ALWAYS, \ newinstr_yes, ft_flags -#endif /* __ASSEMBLY__ */ +#endif /* __ASSEMBLER__ */ #endif /* _ASM_X86_ALTERNATIVE_H */ |