3.16.68-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski <luto@xxxxxxxxxx> commit c28454332fe0b65e22c3a2717e5bf05b5b47ca20 upstream. 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 <luto@xxxxxxxxxx> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/99407f0ac7fa3ab03a3d31ce076d47b5c2f44795.1447361906.git.luto@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/x86/include/asm/jump_label.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- 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>
