From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E177FCC6B3A for ; Thu, 15 Oct 2026 11:23:00 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xHJWK-00025g-JA; Thu, 15 Oct 2026 07:21:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xHJWF-00023n-8F for qemu-devel@nongnu.org; Thu, 15 Oct 2026 07:21:08 -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 1xHJWC-000432-9f for qemu-devel@nongnu.org; Thu, 15 Oct 2026 07:21:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1792063263; 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=Qlpt+MdO11lcCowkxz4GM0uQ0zXlAJAaoHffBaEqEvw=; b=AAeK8ph0IcBEoj0T6zJXKtN09OWN9SVhIBKVtxQPB9kLzaTl9jM4bmvZDu/GGdr47uPT1w hDPd2XNEo+KExkWB9ZujscexvlCtVaPQ18oGORVZzrkvWUFX9rmb+foWciZuzFRrRlHif2 xcSa0ZVcds2kHq+LWtFcujc9tPkSavo= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-610-PfGTlsMXMLqvgF-v3E13ww-1; Thu, 15 Oct 2026 11:21:00 +0000 X-MC-Unique: PfGTlsMXMLqvgF-v3E13ww-1 X-Mimecast-MFC-AGG-ID: PfGTlsMXMLqvgF-v3E13ww_1792063259 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B4AAB1956071; Thu, 15 Oct 2026 11:20:58 +0000 (UTC) Received: from berrange.csb (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E90881800677; Thu, 15 Oct 2026 11:20:54 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Michael Roth , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Fabiano Rosas , Richard Henderson , "Dr. David Alan Gilbert" , Paolo Bonzini , Markus Armbruster , Pierrick Bouvier , Eric Blake , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Laurent Vivier Subject: [PATCH 02/21] system: move SIGBUS signal handling to signal.c Date: Thu, 15 Oct 2026 12:20:25 +0100 Message-ID: <20261015112044.1999748-3-berrange@redhat.com> In-Reply-To: <20261015112044.1999748-1-berrange@redhat.com> References: <20261015112044.1999748-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 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: 10 X-Spam_score: 1.0 X-Spam_bar: + X-Spam_report: (1.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.24, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Introduce a new file 'system/signal.c' to hold the SIGBUS signal handler, since subsequent commits are going to expand the signal handling logic somewhat. The existing copyright header/license boilerplate is retained instead of a SPDX tag, to respect historic context. Signed-off-by: Daniel P. Berrangé --- MAINTAINERS | 2 + include/system/signal.h | 25 ++++++++++ system/cpus.c | 76 +--------------------------- system/meson.build | 1 + system/signal.c | 107 ++++++++++++++++++++++++++++++++++++++++ 5 files changed, 136 insertions(+), 75 deletions(-) create mode 100644 include/system/signal.h create mode 100644 system/signal.c diff --git a/MAINTAINERS b/MAINTAINERS index fc60193aa3f..6b5aafe43b1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -553,6 +553,7 @@ F: include/exec/target_long.h F: include/qemu/accel.h F: include/system/accel-*.h F: include/system/cpus.h +F: include/system/signal.h F: include/accel/accel-*.h F: accel/accel-*.? F: accel/dummy-cpus.? @@ -562,6 +563,7 @@ F: cpu-common.c F: cpu-target.c F: qapi/accelerator.json F: system/cpus.c +F: system/signal.c Apple Silicon HVF CPUs M: Alexander Graf diff --git a/include/system/signal.h b/include/system/signal.h new file mode 100644 index 00000000000..f8d00221bcf --- /dev/null +++ b/include/system/signal.h @@ -0,0 +1,25 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +void qemu_init_sigbus(void); diff --git a/system/cpus.c b/system/cpus.c index e11a5aab6a6..b231ca4c4ac 100644 --- a/system/cpus.c +++ b/system/cpus.c @@ -39,28 +39,11 @@ #include "system/runstate.h" #include "system/cpu-timers.h" #include "system/whpx.h" +#include "system/signal.h" #include "hw/core/boards.h" #include "hw/core/hw-error.h" #include "trace.h" -#ifdef CONFIG_LINUX - -#include - -#ifndef PR_MCE_KILL -#define PR_MCE_KILL 33 -#endif - -#ifndef PR_MCE_KILL_SET -#define PR_MCE_KILL_SET 1 -#endif - -#ifndef PR_MCE_KILL_EARLY -#define PR_MCE_KILL_EARLY 1 -#endif - -#endif /* CONFIG_LINUX */ - /* The Big QEMU Lock (BQL) */ static QemuMutex bql; @@ -302,63 +285,6 @@ void cpu_handle_guest_debug(CPUState *cpu) } } -#ifdef CONFIG_LINUX -static void sigbus_reraise(void) -{ - sigset_t set; - struct sigaction action; - - memset(&action, 0, sizeof(action)); - action.sa_handler = SIG_DFL; - if (!sigaction(SIGBUS, &action, NULL)) { - raise(SIGBUS); - sigemptyset(&set); - sigaddset(&set, SIGBUS); - pthread_sigmask(SIG_UNBLOCK, &set, NULL); - } - perror("Failed to re-raise SIGBUS!"); - abort(); -} - -static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx) -{ - if (siginfo->si_code != BUS_MCEERR_AO && siginfo->si_code != BUS_MCEERR_AR) { - sigbus_reraise(); - } - - if (current_cpu) { - /* Called asynchronously in VCPU thread. */ - if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code, siginfo->si_addr)) { - sigbus_reraise(); - } - } else { - /* Called synchronously (via signalfd) in main thread. */ - if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) { - sigbus_reraise(); - } - } -} - -static void qemu_init_sigbus(void) -{ - struct sigaction action; - - /* - * ALERT: when modifying this, take care that SIGBUS forwarding in - * qemu_prealloc_mem() will continue working as expected. - */ - memset(&action, 0, sizeof(action)); - action.sa_flags = SA_SIGINFO; - action.sa_sigaction = sigbus_handler; - sigaction(SIGBUS, &action, NULL); - - prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0); -} -#else /* !CONFIG_LINUX */ -static void qemu_init_sigbus(void) -{ -} -#endif /* !CONFIG_LINUX */ static QemuThread io_thread; diff --git a/system/meson.build b/system/meson.build index a6ba7a04f7d..1829de3d25b 100644 --- a/system/meson.build +++ b/system/meson.build @@ -24,6 +24,7 @@ system_ss.add(files( 'rtc.c', 'runstate-action.c', 'runstate.c', + 'signal.c', 'watchpoint.c', )) diff --git a/system/signal.c b/system/signal.c new file mode 100644 index 00000000000..6d69db2bc79 --- /dev/null +++ b/system/signal.c @@ -0,0 +1,107 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "qemu/osdep.h" +#include "system/signal.h" +#include "hw/core/cpu.h" +#include "system/kvm.h" + +#ifdef CONFIG_LINUX + +#include + +#ifndef PR_MCE_KILL +#define PR_MCE_KILL 33 +#endif + +#ifndef PR_MCE_KILL_SET +#define PR_MCE_KILL_SET 1 +#endif + +#ifndef PR_MCE_KILL_EARLY +#define PR_MCE_KILL_EARLY 1 +#endif + +#endif /* CONFIG_LINUX */ + + +#ifdef CONFIG_LINUX +static void sigbus_reraise(void) +{ + sigset_t set; + struct sigaction action; + + memset(&action, 0, sizeof(action)); + action.sa_handler = SIG_DFL; + if (!sigaction(SIGBUS, &action, NULL)) { + raise(SIGBUS); + sigemptyset(&set); + sigaddset(&set, SIGBUS); + pthread_sigmask(SIG_UNBLOCK, &set, NULL); + } + perror("Failed to re-raise SIGBUS!"); + abort(); +} + +static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx) +{ + if (siginfo->si_code != BUS_MCEERR_AO && + siginfo->si_code != BUS_MCEERR_AR) { + sigbus_reraise(); + } + + if (current_cpu) { + /* Called asynchronously in VCPU thread. */ + if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code, + siginfo->si_addr)) { + sigbus_reraise(); + } + } else { + /* Called synchronously (via signalfd) in main thread. */ + if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) { + sigbus_reraise(); + } + } +} + +void qemu_init_sigbus(void) +{ + struct sigaction action; + + /* + * ALERT: when modifying this, take care that SIGBUS forwarding in + * qemu_prealloc_mem() will continue working as expected. + */ + memset(&action, 0, sizeof(action)); + action.sa_flags = SA_SIGINFO; + action.sa_sigaction = sigbus_handler; + sigaction(SIGBUS, &action, NULL); + + prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0); +} +#else /* !CONFIG_LINUX */ +void qemu_init_sigbus(void) +{ +} +#endif /* !CONFIG_LINUX */ -- 2.56.0