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Diffstat (limited to 'arch/x86/include/asm/alternative.h')
-rw-r--r--arch/x86/include/asm/alternative.h30
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