From patchwork Fri May 13 15:49:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 12849022 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 lists.gnu.org (lists.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 127D3C433EF for ; Fri, 13 May 2022 15:56:40 +0000 (UTC) Received: from localhost ([::1]:44026 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1npXeh-0007Sk-1S for qemu-devel@archiver.kernel.org; Fri, 13 May 2022 11:56:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47692) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1npXXZ-00061x-94 for qemu-devel@nongnu.org; Fri, 13 May 2022 11:49:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:36254) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1npXXX-0000h8-PA for qemu-devel@nongnu.org; Fri, 13 May 2022 11:49:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652456955; 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=+tH2fL2NxCWKTyy4UAazFMEt0it3D7+Rs6aTLpCh0Ts=; b=Oj4rLOz1NmyRJAbFQBRMFDhcAmIzYrqoQiK9wU4KwnRGAy/Tukr8S2maQ14YcxMee0zkIo +PjXFGzu83LJkZrIVIoPz6/XbgzMOzWY3ezy/hellJ2L30/W38QxRv9Tx2fA8iub5DkhiF WuPBhUutt6l4VQPj7k5aaujI2+oOgzI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-128-YzQCgLI8MZ6tvEctnf_d4Q-1; Fri, 13 May 2022 11:49:11 -0400 X-MC-Unique: YzQCgLI8MZ6tvEctnf_d4Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 14C7B801210 for ; Fri, 13 May 2022 15:49:11 +0000 (UTC) Received: from localhost.localdomain.com (unknown [10.33.36.124]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1851B1467E50; Fri, 13 May 2022 15:49:09 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Thomas Huth , Paolo Bonzini , Laurent Vivier , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= Subject: [PATCH v2 2/2] tests/qtest: use prctl(PR_SET_PDEATHSIG) as fallback to kill QEMU Date: Fri, 13 May 2022 16:49:06 +0100 Message-Id: <20220513154906.206715-3-berrange@redhat.com> In-Reply-To: <20220513154906.206715-1-berrange@redhat.com> References: <20220513154906.206715-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 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: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Although we register a ABRT handler to kill off QEMU when g_assert() triggers, we want an extra safety net. The QEMU process might be non-functional and thus not have responded to SIGTERM. The test script might also have crashed with SEGV, in which case the cleanup handlers won't ever run. Using the Linux specific prctl(PR_SET_PDEATHSIG) syscall, we can ensure that QEMU gets sent SIGKILL as soon as the controlling qtest exits, if nothing else has correctly told it to quit. Note, technically the death signal is sent when the *thread* that called fork() exits. IOW, if you are calling qtest_init() in one thread, letting that thread exit, and then expecting to run qtest_quit() in a different thread, things are not going to work out. Fortunately that is not a scenario that exists in qtests, as pairs of qtest_init and qtest_quit are always called from the same thread. Signed-off-by: Daniel P. Berrangé Reviewed-by: Thomas Huth --- tests/qtest/libqtest.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c index 4a4697c0d1..2e49618454 100644 --- a/tests/qtest/libqtest.c +++ b/tests/qtest/libqtest.c @@ -19,6 +19,9 @@ #include #include #include +#ifdef __linux__ +#include +#endif /* __linux__ */ #include "libqtest.h" #include "libqmp.h" @@ -301,6 +304,20 @@ QTestState *qtest_init_without_qmp_handshake(const char *extra_args) s->expected_status = 0; s->qemu_pid = fork(); if (s->qemu_pid == 0) { +#ifdef __linux__ + /* + * Although we register a ABRT handler to kill off QEMU + * when g_assert() triggers, we want an extra safety + * net. The QEMU process might be non-functional and + * thus not have responded to SIGTERM. The test script + * might also have crashed with SEGV, in which case the + * cleanup handlers won't ever run. + * + * This PR_SET_PDEATHSIG setup will ensure any remaining + * QEMU will get terminated with SIGKILL in these cases. + */ + prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); +#endif /* __linux__ */ if (!g_setenv("QEMU_AUDIO_DRV", "none", true)) { exit(1); }