diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2019-03-18 16:33:07 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-04-03 10:39:46 +0300 |
| commit | ff05ab2305aaeb21a3002ae95a17e176c198b71b (patch) | |
| tree | c65ef588d4ec4bc4a590a07a69a394c2c4a046c5 /arch/x86/include/asm | |
| parent | b69656fa7ea2f75e47d7bd5b9430359fa46488af (diff) | |
| download | linux-ff05ab2305aaeb21a3002ae95a17e176c198b71b.tar.xz | |
x86/nospec, objtool: Introduce ANNOTATE_IGNORE_ALTERNATIVE
To facillitate other usage of ignoring alternatives; rename
ANNOTATE_NOSPEC_IGNORE to ANNOTATE_IGNORE_ALTERNATIVE.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/alternative-asm.h | 11 | ||||
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 28 |
3 files changed, 30 insertions, 19 deletions
diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h index 31b627b43a8e..464034db299f 100644 --- a/arch/x86/include/asm/alternative-asm.h +++ b/arch/x86/include/asm/alternative-asm.h @@ -20,6 +20,17 @@ #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 diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 4c74073a19cc..094fbc9c0b1c 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -45,6 +45,16 @@ #define LOCK_PREFIX "" #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" + struct alt_instr { s32 instr_offset; /* original instruction */ s32 repl_offset; /* offset to replacement instruction */ diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index dad12b767ba0..daf25b60c9e3 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -11,6 +11,15 @@ #include <asm/msr-index.h> /* + * This should be used immediately before a retpoline alternative. It tells + * objtool where the retpolines are so that it can make sense of the control + * flow by just reading the original instruction(s) and ignoring the + * alternatives. + */ +#define ANNOTATE_NOSPEC_ALTERNATIVE \ + ANNOTATE_IGNORE_ALTERNATIVE + +/* * Fill the CPU return stack buffer. * * Each entry in the RSB, if used for a speculative 'ret', contains an @@ -57,19 +66,6 @@ #ifdef __ASSEMBLY__ /* - * This should be used immediately before a retpoline alternative. It tells - * objtool where the retpolines are so that it can make sense of the control - * flow by just reading the original instruction(s) and ignoring the - * alternatives. - */ -.macro ANNOTATE_NOSPEC_ALTERNATIVE - .Lannotate_\@: - .pushsection .discard.nospec - .long .Lannotate_\@ - . - .popsection -.endm - -/* * This should be used immediately before an indirect jump/call. It tells * objtool the subsequent indirect jump/call is vouched safe for retpoline * builds. @@ -152,12 +148,6 @@ #else /* __ASSEMBLY__ */ -#define ANNOTATE_NOSPEC_ALTERNATIVE \ - "999:\n\t" \ - ".pushsection .discard.nospec\n\t" \ - ".long 999b - .\n\t" \ - ".popsection\n\t" - #define ANNOTATE_RETPOLINE_SAFE \ "999:\n\t" \ ".pushsection .discard.retpoline_safe\n\t" \ |