From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:47892 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751754AbdHCV5V (ORCPT ); Thu, 3 Aug 2017 17:57:21 -0400 Subject: Patch "perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero" has been added to the 4.4-stable tree To: adrian.hunter@intel.com, acme@redhat.com, ak@linux.intel.com, gregkh@linuxfoundation.org Cc: , From: Date: Thu, 03 Aug 2017 14:56:41 -0700 Message-ID: <1501797401129149@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-intel-pt-ensure-never-to-set-last_ip-when-packet-count-is-zero.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From f952eaceb089b691eba7c4e13686e742a8f26bf5 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 26 May 2017 11:17:07 +0300 Subject: perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero From: Adrian Hunter commit f952eaceb089b691eba7c4e13686e742a8f26bf5 upstream. Intel PT uses IP compression based on the last IP. For decoding purposes, 'last IP' is not updated when a branch target has been suppressed, which is indicated by IPBytes == 0. IPBytes is stored in the packet 'count', so ensure never to set 'last_ip' when packet 'count' is zero. Signed-off-by: Adrian Hunter Cc: Andi Kleen Link: http://lkml.kernel.org/r/1495786658-18063-7-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1438,7 +1438,8 @@ static int intel_pt_walk_psbend(struct i case INTEL_PT_FUP: decoder->pge = true; - intel_pt_set_last_ip(decoder); + if (decoder->packet.count) + intel_pt_set_last_ip(decoder); break; case INTEL_PT_MODE_TSX: @@ -1724,8 +1725,9 @@ next: static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder) { - return decoder->have_last_ip || decoder->packet.count == 0 || - decoder->packet.count == 3 || decoder->packet.count == 6; + return decoder->packet.count && + (decoder->have_last_ip || decoder->packet.count == 3 || + decoder->packet.count == 6); } /* Walk PSB+ packets to get in sync. */ Patches currently in stable-queue which might be from adrian.hunter@intel.com are queue-4.4/perf-intel-pt-ensure-never-to-set-last_ip-when-packet-count-is-zero.patch queue-4.4/perf-intel-pt-use-fup-always-when-scanning-for-an-ip.patch queue-4.4/perf-intel-pt-fix-last_ip-usage.patch queue-4.4/perf-intel-pt-fix-ip-compression.patch