From nobody Sun Dec 14 12:13:42 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=reject dis=none) header.from=google.com ARC-Seal: i=1; a=rsa-sha256; t=1765584824; cv=none; d=zohomail.com; s=zohoarc; b=KIX93FCSqawBb1o3xxUdsXYIK7wwbC3KKXYAekXE2vwjQzq+RbeIBCjCgda3SzyDOOqwZT/3T0RqEpOfDRpHt7oQKW953zQd8w4foj0yb78Ll48eZvbf85UEzNRKU+DN0nnIz7XrnEaADohUFvpjKDJm2DkvHHaxmu6kilqmnd0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1765584824; h=Content-Type:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=sl9CNn1EVZEpq7y7cqXda6K3glgb23SOapyyZsDMnjg=; b=YjBHRm1ySC6OXddgXSrjWfNh1+RZX+/1V6tjZyBgMv8rLG914VswABkDxeiEqy1Ht8PlgjQz5fInGEjLMaHB8Z+/6+icp/oIFSeRIUlU2RzfS2Dwy8CeT+oAZ+kmdBzwNCZcig6cM1J6C0EMUg62n2ldzFpv7LbEPJ6j1UT3DZA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=reject dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1765584824390632.4190881590747; Fri, 12 Dec 2025 16:13:44 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vUDFo-00046C-6H; Fri, 12 Dec 2025 19:12:56 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <3gq88aQoKCiUNBSDNPSDPTHPPHMF.DPNRFNV-EFWFMOPOHOV.PSH@flex--marcmorcos.bounces.google.com>) id 1vUDFm-00044C-21 for qemu-devel@nongnu.org; Fri, 12 Dec 2025 19:12:54 -0500 Received: from mail-pj1-x1049.google.com ([2607:f8b0:4864:20::1049]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from <3gq88aQoKCiUNBSDNPSDPTHPPHMF.DPNRFNV-EFWFMOPOHOV.PSH@flex--marcmorcos.bounces.google.com>) id 1vUDFk-0006kw-D9 for qemu-devel@nongnu.org; Fri, 12 Dec 2025 19:12:53 -0500 Received: by mail-pj1-x1049.google.com with SMTP id 98e67ed59e1d1-34a907477b3so3146822a91.2 for ; Fri, 12 Dec 2025 16:12:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1765584770; x=1766189570; darn=nongnu.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=sl9CNn1EVZEpq7y7cqXda6K3glgb23SOapyyZsDMnjg=; b=4pZ1FmmzyE1y2KxjngM/SwFJJKXIK4JsJXyKbkDzP9tDfZIaZXA928X8Qhmd3hGehE WsY/AZjbtD1hTR2xVZidDvJGiHqnMrFyw9HGFsVS2fy8lriY10CezXBkLaa3J+aaSbzB ziuKpwpRvQN32T//+ms7/8CWTNGZT5guVrMSWDmSLOaHWXiOAHiw9f7oweIy9DkusKLb psEaGH8Unxs2/xgyUkfTd1Yrg5mIRaRQh9VGf3T2WPqivuSbwHA3OF3dQxo9Y28BvUvl VgWe6mFYhAXvzYcqKlTp0ILtm+zQ9GZ/yz0/vJsmNl87Acct5fi6PZ8Opb1SlHf7YAYg hlug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1765584770; x=1766189570; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=sl9CNn1EVZEpq7y7cqXda6K3glgb23SOapyyZsDMnjg=; b=OfoybIOykaUruvi/WtIgo8kB7GZt2B1z+E7jQJFndE5qhlipYkqROEpz+Rpg6oMFEz 6ja/+x/GCiEitshfQfd5hpub5thFO0gve9Aa2Mw9J2vpAYu3Z64UZyW5jR5mHd0ikAWI GLJgsXXBjkEzts6CAnGORjeE653EE/VDzGwiyr3WwIzXIotQOY7eM6O1E1PRI652ZkMu LBqRXx54UyME32Bzfu+Z8yBtc01zw+ZnaSrq+FOltTfEivWZLBLisf0ODvF64vcciw1d sBMYXLiq7a5z1Y1sV2F+cu4hhVc5dlcKhSClf2MW4CbWvVEt6yGtolyY5XuBP14T++Op w9PQ== X-Forwarded-Encrypted: i=1; AJvYcCWoICTVtfrbKheEXjKtZZFM9y3wR44tyZl2QcCrFlv8s66AAAwQ9mJ159+clmO2bE+23pIiiH/27vl8@nongnu.org X-Gm-Message-State: AOJu0YxOl7BdDlh9By9FOuskPQcGDKKKGpX9KoFDff4ApnnUavP4gS0D HIEta+dW6FXBEVejODDtMcC+B1eOZznocajxOAPfkHzA83WVt56aJGlQ49K0BTcA1ZrMaoMXNzi vsdTxBY4gFph1aGzCu1bAFA== X-Google-Smtp-Source: AGHT+IFZgGy/54LFCIOGtITvodQtwjMNPJrpkO2x08T+X+pQSvoE39BYo7+RVpUI+PyJkSXvQR/0R145JbF7QwnW X-Received: from dlbqe2.prod.google.com ([2002:a05:7023:b82:b0:11b:13:9d43]) (user=marcmorcos job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:78f:b0:11f:2c69:3e with SMTP id a92af1059eb24-11f35475ccamr2979494c88.6.1765584770388; Fri, 12 Dec 2025 16:12:50 -0800 (PST) Date: Sat, 13 Dec 2025 00:12:33 +0000 In-Reply-To: <20251213001234.2039232-1-marcmorcos@google.com> Mime-Version: 1.0 References: <20251213001234.2039232-1-marcmorcos@google.com> X-Mailer: git-send-email 2.52.0.239.gd5f0c6e74e-goog Message-ID: <20251213001234.2039232-4-marcmorcos@google.com> Subject: [PATCH 3/4] qmp: Fix thread race From: Marc Morcos To: maintainer_email_from_script@google.com Cc: cc_list_from_script@google.com, qemu-devel@nongnu.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::1049; envelope-from=3gq88aQoKCiUNBSDNPSDPTHPPHMF.DPNRFNV-EFWFMOPOHOV.PSH@flex--marcmorcos.bounces.google.com; helo=mail-pj1-x1049.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: 1765584825101158500 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