1 files changed, 5 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/perf_event.h b/arch/powerpc/include/asm/perf_event.h
index 5c16b891d501..0bb23725b1e7 100644
--- a/arch/powerpc/include/asm/perf_event.h
+++ b/arch/powerpc/include/asm/perf_event.h
@@ -26,8 +26,13 @@
 #include <asm/ptrace.h>
 #include <asm/reg.h>
 
+/*
+ * Overload regs->result to specify whether we should use the MSR (result
+ * is zero) or the SIAR (result is non zero).
+ */
 #define perf_arch_fetch_caller_regs(regs, __ip)                 \
         do {                                                    \
+                (regs)->result = 0;                             \
                 (regs)->nip = __ip;                             \
                 (regs)->gpr[1] = *(unsigned long *)__get_SP();  \
                 asm volatile("mfmsr %0" : "=r" ((regs)->msr));  \