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Subject[PATCH 2/4] perf/x86_64: get_regs_user: Do report user_regs->cx while we are in syscall
Date
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 <dvlasenk@redhat.com>
CC: Jiri Olsa <jolsa@redhat.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Paul Mackerras <paulus@samba.org>
CC: Ingo Molnar <mingo@redhat.com>
CC: Arnaldo Carvalho de Melo <acme@kernel.org>
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
---
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 7ab198a..a8d4e48 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) ?
--
1.8.1.4


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