From: David S. Miller Date: Mon, 29 Mar 2010 20:08:52 +0000 (-0700) Subject: sparc64: Properly truncate pt_regs framepointer in perf callback. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9e8307ecaf9f8c8b5b3b22145021204c4e73114a;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git sparc64: Properly truncate pt_regs framepointer in perf callback. For 32-bit processes, we save the full 64-bits of the regs in pt_regs. But unlike when the userspace actually does load and store instructions, the top 32-bits don't get automatically truncated by the cpu in kernel mode (because the kernel doesn't execute with PSTATE_AM address masking enabled). So we have to do it by hand. Reported-by: Frederic Weisbecker Signed-off-by: David S. Miller --- diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c index 9f2b2bac8b2b..610112ec518a 100644 --- a/arch/sparc/kernel/perf_event.c +++ b/arch/sparc/kernel/perf_event.c @@ -1337,7 +1337,7 @@ static void perf_callchain_user_32(struct pt_regs *regs, callchain_store(entry, PERF_CONTEXT_USER); callchain_store(entry, regs->tpc); - ufp = regs->u_regs[UREG_I6]; + ufp = regs->u_regs[UREG_I6] & 0xffffffffUL; do { struct sparc_stackf32 *usf, sf; unsigned long pc;