This is a note to let you know that I've just added the patch titled perf intel-pt: Fix FUP packet state to the 4.14-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-fix-fup-packet-state.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 401136bb084fd021acd9f8c51b52fe0a25e326b2 Mon Sep 17 00:00:00 2001 From: Adrian Hunter <adrian.hunter@xxxxxxxxx> Date: Fri, 10 Jul 2020 18:10:53 +0300 Subject: perf intel-pt: Fix FUP packet state From: Adrian Hunter <adrian.hunter@xxxxxxxxx> commit 401136bb084fd021acd9f8c51b52fe0a25e326b2 upstream. While walking code towards a FUP ip, the packet state is INTEL_PT_STATE_FUP or INTEL_PT_STATE_FUP_NO_TIP. That was mishandled resulting in the state becoming INTEL_PT_STATE_IN_SYNC prematurely. The result was an occasional lost EXSTOP event. Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: http://lore.kernel.org/lkml/20200710151104.15137-2-adrian.hunter@xxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 21 ++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1129,6 +1129,7 @@ static int intel_pt_walk_fup(struct inte return 0; if (err == -EAGAIN || intel_pt_fup_with_nlip(decoder, &intel_pt_insn, ip, err)) { + decoder->pkt_state = INTEL_PT_STATE_IN_SYNC; if (intel_pt_fup_event(decoder)) return 0; return -EAGAIN; @@ -1780,17 +1781,13 @@ next: } if (decoder->set_fup_mwait) no_tip = true; + if (no_tip) + decoder->pkt_state = INTEL_PT_STATE_FUP_NO_TIP; + else + decoder->pkt_state = INTEL_PT_STATE_FUP; err = intel_pt_walk_fup(decoder); - if (err != -EAGAIN) { - if (err) - return err; - if (no_tip) - decoder->pkt_state = - INTEL_PT_STATE_FUP_NO_TIP; - else - decoder->pkt_state = INTEL_PT_STATE_FUP; - return 0; - } + if (err != -EAGAIN) + return err; if (no_tip) { no_tip = false; break; @@ -2375,15 +2372,11 @@ const struct intel_pt_state *intel_pt_de err = intel_pt_walk_tip(decoder); break; case INTEL_PT_STATE_FUP: - decoder->pkt_state = INTEL_PT_STATE_IN_SYNC; err = intel_pt_walk_fup(decoder); if (err == -EAGAIN) err = intel_pt_walk_fup_tip(decoder); - else if (!err) - decoder->pkt_state = INTEL_PT_STATE_FUP; break; case INTEL_PT_STATE_FUP_NO_TIP: - decoder->pkt_state = INTEL_PT_STATE_IN_SYNC; err = intel_pt_walk_fup(decoder); if (err == -EAGAIN) err = intel_pt_walk_trace(decoder); Patches currently in stable-queue which might be from adrian.hunter@xxxxxxxxx are queue-4.14/perf-intel-pt-fix-fup-packet-state.patch