From 5df71b396b2d1fdd9d9f5a33e2eda5dc27c5632d Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 10 Apr 2015 15:06:57 +0200 Subject: [PATCH] perf/x86/64: Do report user_regs->cx while we are in syscall, in get_regs_user() Yes, it is true that cx contains return address. It's not clear why we trash it. Stop doing that. Signed-off-by: Denys Vlasenko Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1428671219-29341-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/perf_regs.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c index 7ab198acc5b8..a8d4e4862ace 100644 --- a/arch/x86/kernel/perf_regs.c +++ b/arch/x86/kernel/perf_regs.c @@ -177,8 +177,6 @@ void perf_get_regs_user(struct perf_regs *regs_user, * than just blindly copying user_regs. */ regs_user->abi = PERF_SAMPLE_REGS_ABI_64; - /* usually contains return address (same as ->ip) */ - regs_user_copy->cx = -1; } else { /* We're probably in an interrupt or exception. */ regs_user->abi = user_64bit_mode(user_regs) ?