[PATCH] powerpc/asm: Mark cr0 as clobbered in mftb()
From: Oliver O'Halloran <oohall@gmail.com>
Date: 2017-07-06 08:46:56
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
The workaround for the CELL timebase bug does not correctly mark cr0 as being clobbered. This can result in GCC making some poor^W completely broken optimisations. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> --- arch/powerpc/include/asm/reg.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 7e50e47375d6..a3b6575c7842 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h@@ -1303,7 +1303,7 @@ static inline void msr_check_and_clear(unsigned long bits) " .llong 0\n" \ ".previous" \ : "=r" (rval) \ - : "i" (CPU_FTR_CELL_TB_BUG), "i" (SPRN_TBRL)); \ + : "i" (CPU_FTR_CELL_TB_BUG), "i" (SPRN_TBRL) : "cr0"); \ rval;}) #else #define mftb() ({unsigned long rval; \
--
2.9.4