From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Adrian Hunter <adrian.hunter@intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: [PATCH 5.15 077/171] perf intel-pt: Fix sync state when a PSB (synchronization) packet is found
Date:   Mon, 13 Dec 2021 10:29:52 +0100
Message-Id: <20211213092947.663677024@linuxfoundation.org>
In-Reply-To: <20211213092945.091487407@linuxfoundation.org>
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From: Adrian Hunter <adrian.hunter@intel.com>

commit ad106a26aef3a95ac7ca88d033b431661ba346ce upstream.

When syncing, it may be that branch packet generation is not enabled at
that point, in which case there will not immediately be a control-flow
packet, so some packets before a control flow packet turns up, get
ignored.  However, the decoder is in sync as soon as a PSB is found, so
the state should be set accordingly.

Fixes: f4aa081949e7b6 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 tools/perf/util/intel-pt-decoder/intel-pt-decoder.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -3607,7 +3607,7 @@ static int intel_pt_sync(struct intel_pt
 	}
 
 	decoder->have_last_ip = true;
-	decoder->pkt_state = INTEL_PT_STATE_NO_IP;
+	decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
 
 	err = intel_pt_walk_psb(decoder);
 	if (err)