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David Alan Gilbert" Cc: "Michael S . Tsirkin" , Marcel Apfelbaum , Markus Armbruster , Marcelo Tosatti , qemu-devel@nongnu.org, kvm@vger.kernel.org, Marc Morcos Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::54a; envelope-from=3_688aQoKCqIOCTEOQTEQUIQQING.EQOSGOW-FGXGNPQPIPW.QTI@flex--marcmorcos.bounces.google.com; helo=mail-pg1-x54a.google.com X-Spam_score_int: -95 X-Spam_score: -9.6 X-Spam_bar: --------- X-Spam_report: (-9.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @google.com) X-ZM-MESSAGEID: 1765584923225158500 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This fixes a thread race involving the monitor in monitor_qmp_event and mon= itor_qapi_event_emit . Signed-off-by: Marc Morcos --- monitor/monitor.c | 11 ++++++++++- monitor/qmp.c | 6 ++++-- 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/monitor/monitor.c b/monitor/monitor.c index c5a5d30877..4bfd72939d 100644 --- a/monitor/monitor.c +++ b/monitor/monitor.c @@ -338,6 +338,7 @@ static void monitor_qapi_event_emit(QAPIEvent event, QD= ict *qdict) { Monitor *mon; MonitorQMP *qmp_mon; + bool do_send =3D false; =20 trace_monitor_protocol_event_emit(event, qdict); QTAILQ_FOREACH(mon, &mon_list, entry) { @@ -346,7 +347,15 @@ static void monitor_qapi_event_emit(QAPIEvent event, Q= Dict *qdict) } =20 qmp_mon =3D container_of(mon, MonitorQMP, common); - if (qmp_mon->commands !=3D &qmp_cap_negotiation_commands) { + do_send =3D false; + + WITH_QEMU_LOCK_GUARD(&mon->mon_lock) { + if (qmp_mon->commands !=3D &qmp_cap_negotiation_commands) { + do_send =3D true; + } + } + + if (do_send) { qmp_send_response(qmp_mon, qdict); } } diff --git a/monitor/qmp.c b/monitor/qmp.c index cb99a12d94..e1419a9efa 100644 --- a/monitor/qmp.c +++ b/monitor/qmp.c @@ -462,8 +462,10 @@ static void monitor_qmp_event(void *opaque, QEMUChrEve= nt event) =20 switch (event) { case CHR_EVENT_OPENED: - mon->commands =3D &qmp_cap_negotiation_commands; - monitor_qmp_caps_reset(mon); + WITH_QEMU_LOCK_GUARD(&mon->common.mon_lock) { + mon->commands =3D &qmp_cap_negotiation_commands; + monitor_qmp_caps_reset(mon); + } data =3D qmp_greeting(mon); qmp_send_response(mon, data); qobject_unref(data); --=20 2.52.0.239.gd5f0c6e74e-goog