diff options
| -rw-r--r-- | arch/arm/include/asm/percpu.h | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h index 968c0a14e0a3..209e6504922e 100644 --- a/arch/arm/include/asm/percpu.h +++ b/arch/arm/include/asm/percpu.h @@ -30,8 +30,15 @@ static inline void set_my_cpu_offset(unsigned long off) static inline unsigned long __my_cpu_offset(void) { unsigned long off; - /* Read TPIDRPRW */ - asm("mrc p15, 0, %0, c13, c0, 4" : "=r" (off) : : "memory"); + register unsigned long *sp asm ("sp"); + + /* + * Read TPIDRPRW. + * We want to allow caching the value, so avoid using volatile and + * instead use a fake stack read to hazard against barrier(). + */ + asm("mrc p15, 0, %0, c13, c0, 4" : "=r" (off) : "Q" (*sp)); + return off; } #define __my_cpu_offset __my_cpu_offset() |