From nobody Sun Sep 28 17:40:13 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=quarantine dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1757527589; cv=none; d=zohomail.com; s=zohoarc; b=lERYFeqMTfmW7kJ9+MfZl7W96Mcza4v0uHsmBeZ3SGr4bBaZWvmbGXi9LCpEVCYm0GgS5ybNUG8iCeFRhw09OdbEznxbT6IG4Ed3U9BQ8lv0eq773bASMRJAI5YBt5NOen08Q57zKrcy/6GeEytcqWmZIWZnf9wveWx7QKmY4aw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1757527589; h=Content-Type:Content-Transfer-Encoding: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=BcrB75/R+NNCB4eg5mAoBzqzkku+VwsQ0AwmZXXftUc=; b=LHNiTSKlpLO083DSfPw3x9z3OdgIJkUM/r6eNaEu/+uelSofM5WpJimWk2bg7nOIj8ZLWBROhUF54vs+3iz6vW9bMBiwWPDPNrzAAIVlI6YKu9s0H9zESi0NCTgHzN0/VUjbjFNwUxZ+Xpa4xEw72WVgWX5nhOiHFguLJkQLE/c= 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=quarantine dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1757527589079480.6302545552295; Wed, 10 Sep 2025 11:06:29 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uwPBA-0007sw-Lt; Wed, 10 Sep 2025 14:04:24 -0400 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 ) id 1uwPB8-0007sJ-4O for qemu-devel@nongnu.org; Wed, 10 Sep 2025 14:04:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uwPB6-0004fV-AH for qemu-devel@nongnu.org; Wed, 10 Sep 2025 14:04:21 -0400 Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-518-0FwO_hZ3O7qQAH7gXF6dSQ-1; Wed, 10 Sep 2025 14:04:13 -0400 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C3C28180047F; Wed, 10 Sep 2025 18:04:11 +0000 (UTC) Received: from toolbx.redhat.com (unknown [10.42.28.57]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id EE4AC1800446; Wed, 10 Sep 2025 18:04:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1757527458; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BcrB75/R+NNCB4eg5mAoBzqzkku+VwsQ0AwmZXXftUc=; b=RPQx6i/p1rRwBv1m9gTh8HyyBgYDpKY73rVYrFNir9TXwfAntpUYfvOezZwVc8czadWMZj Z/07I9N/WTCYupBPFPw06QFsDc4wW3ZDaksnIJSu5g5WKqU3WNNgk4hAnaB2Ip2O5yBvwI CSq8M2Vk3SKz16V3xnppYNyzVV0Ie/g= X-MC-Unique: 0FwO_hZ3O7qQAH7gXF6dSQ-1 X-Mimecast-MFC-AGG-ID: 0FwO_hZ3O7qQAH7gXF6dSQ_1757527452 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, Hanna Reitz , Kevin Wolf , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Christian Schoenebeck , Richard Henderson , Manos Pitsidianakis , Stefan Weil , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Gerd Hoffmann , Paolo Bonzini , Markus Armbruster , "Dr. David Alan Gilbert" , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Subject: [PATCH v3 02/20] monitor: initialize global data from a constructor Date: Wed, 10 Sep 2025 19:03:39 +0100 Message-ID: <20250910180357.320297-3-berrange@redhat.com> In-Reply-To: <20250910180357.320297-1-berrange@redhat.com> References: <20250910180357.320297-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 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=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-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, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 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 @redhat.com) X-ZM-MESSAGEID: 1757527595345116600 Some monitor functions, most notably, monitor_cur() rely on global data being initialized by 'monitor_init_globals()'. The latter is called relatively late in startup. If code triggers error_report() before monitor_init_globals() is called, QEMU will abort when accessing the uninitialized monitor mutex. The critical monitor global data must be initialized from a constructor function, to improve the guarantee that it is done before any possible calls to monitor_cur(). Not only that, but the constructor must be marked to run before the default constructor in case any of them trigger error reporting. Note in particular that the RCU constructor will spawn a background thread so we might even have non-constructor QEMU code running concurrently with other constructors. Reviewed-by: Richard Henderson Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Daniel P. Berrang=C3=A9 Reviewed-by: Markus Armbruster --- monitor/monitor.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/monitor/monitor.c b/monitor/monitor.c index c5a5d30877..da54e1b1ce 100644 --- a/monitor/monitor.c +++ b/monitor/monitor.c @@ -704,18 +704,22 @@ void monitor_cleanup(void) } } =20 -static void monitor_qapi_event_init(void) +/* + * Initialize static vars that have no deps on external + * module initialization, and are required for external + * functions to call things like monitor_cur() + */ +static void __attribute__((__constructor__(QEMU_CONSTRUCTOR_EARLY))) +monitor_init_static(void) { + qemu_mutex_init(&monitor_lock); + coroutine_mon =3D g_hash_table_new(NULL, NULL); monitor_qapi_event_state =3D g_hash_table_new(qapi_event_throttle_hash, qapi_event_throttle_equal); } =20 void monitor_init_globals(void) { - monitor_qapi_event_init(); - qemu_mutex_init(&monitor_lock); - coroutine_mon =3D g_hash_table_new(NULL, NULL); - /* * The dispatcher BH must run in the main loop thread, since we * have commands assuming that context. It would be nice to get --=20 2.50.1