diff options
| author | Andy Lutomirski <[email protected]> | 2015-11-12 12:59:02 -0800 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-11-24 09:56:43 +0100 |
| commit | c28454332fe0b65e22c3a2717e5bf05b5b47ca20 (patch) | |
| tree | 15dcf6d8644c7e31c7505ce071a20117d6c6080a | |
| parent | ed11a7f1b3bd482bd7d6ef7bc2859c41fb43b9ee (diff) | |
x86/asm: Error out if asm/jump_label.h is included inappropriately
Rather than potentially generating incorrect code on a
non-HAVE_JUMP_LABEL kernel if someone includes asm/jump_label.h,
error out.
Signed-off-by: Andy Lutomirski <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/99407f0ac7fa3ab03a3d31ce076d47b5c2f44795.1447361906.git.luto@kernel.org
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/include/asm/jump_label.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h index 5daeca3d0f9e..96872dc96597 100644 --- a/arch/x86/include/asm/jump_label.h +++ b/arch/x86/include/asm/jump_label.h @@ -1,6 +1,19 @@ #ifndef _ASM_X86_JUMP_LABEL_H #define _ASM_X86_JUMP_LABEL_H +#ifndef HAVE_JUMP_LABEL +/* + * For better or for worse, if jump labels (the gcc extension) are missing, + * then the entire static branch patching infrastructure is compiled out. + * If that happens, the code in here will malfunction. Raise a compiler + * error instead. + * + * In theory, jump labels and the static branch patching infrastructure + * could be decoupled to fix this. + */ +#error asm/jump_label.h included on a non-jump-label kernel +#endif + #ifndef __ASSEMBLY__ #include <linux/stringify.h> |