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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A011C433DF for ; Mon, 6 Jul 2020 07:30:24 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 579D2206CD for ; Mon, 6 Jul 2020 07:30:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XE3p99cp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 579D2206CD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34906 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jsLa3-0004kR-HY for qemu-devel@archiver.kernel.org; Mon, 06 Jul 2020 03:30:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47286) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jsLYY-0003PK-6E for qemu-devel@nongnu.org; Mon, 06 Jul 2020 03:28:51 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:35024 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jsLYU-0004Iz-G6 for qemu-devel@nongnu.org; Mon, 06 Jul 2020 03:28:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594020525; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:content-type:content-type:in-reply-to:in-reply-to: references:references; bh=36Lm0Bi7svE+whLJ15hKmgqYhOIWjqV9aJsJr4usng4=; b=XE3p99cpPi4lkxuWh2eNNK09UMHlnKWQg7Dm5m3WwmDk/vGj8fnSFYJOxVBWkH18KFx9YL sC4UfaCBSonVw5K4f9GR1yJPgUKoB40Igs2DUBlt7dZl6GW1rSFirsrNVw0ytwD8Ao6juK DUTpnUjYIBxPlB7hoIsJFNCC6vwyU+Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-427-dddrdE6nPraz4zQ06hwXvg-1; Mon, 06 Jul 2020 03:28:41 -0400 X-MC-Unique: dddrdE6nPraz4zQ06hwXvg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 63A21EC1A0; Mon, 6 Jul 2020 07:28:40 +0000 (UTC) Received: from thuth.com (ovpn-112-144.ams2.redhat.com [10.36.112.144]) by smtp.corp.redhat.com (Postfix) with ESMTP id 58D8B5D9CC; Mon, 6 Jul 2020 07:28:39 +0000 (UTC) From: Thomas Huth To: Peter Maydell Subject: [PULL 1/6] fuzz: fix broken qtest check at rcu_disable_atfork Date: Mon, 6 Jul 2020 09:28:30 +0200 Message-Id: <20200706072835.23582-2-thuth@redhat.com> In-Reply-To: <20200706072835.23582-1-thuth@redhat.com> References: <20200706072835.23582-1-thuth@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=thuth@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Received-SPF: pass client-ip=207.211.31.81; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/06 01:39:15 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexander Bulekov , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Alexander Bulekov The qtest_enabled check introduced in d6919e4 always returns false, as it is called prior to configure_accelerators(). Instead of trying to skip rcu_disable_atfork in qemu_main, simply call rcu_enable_atfork in the fuzzer, after qemu_main returns. Reported-by: Thomas Huth Signed-off-by: Alexander Bulekov Message-Id: <20200618160516.2817-1-alxndr@bu.edu> Signed-off-by: Thomas Huth --- softmmu/vl.c | 12 +----------- tests/qtest/fuzz/fuzz.c | 3 +++ 2 files changed, 4 insertions(+), 11 deletions(-) diff --git a/softmmu/vl.c b/softmmu/vl.c index 3e15ee2435..9da2e23144 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -3832,17 +3832,7 @@ void qemu_init(int argc, char **argv, char **envp) machine_class); os_daemonize(); - - /* - * If QTest is enabled, keep the rcu_atfork enabled, since system processes - * may be forked testing purposes (e.g. fork-server based fuzzing) The fork - * should happen before a signle cpu instruction is executed, to prevent - * deadlocks. See commit 73c6e40, rcu: "completely disable pthread_atfork - * callbacks as soon as possible" - */ - if (!qtest_enabled()) { - rcu_disable_atfork(); - } + rcu_disable_atfork(); if (pid_file && !qemu_write_pidfile(pid_file, &err)) { error_reportf_err(err, "cannot create PID file: "); diff --git a/tests/qtest/fuzz/fuzz.c b/tests/qtest/fuzz/fuzz.c index a44fe479db..a36d9038e0 100644 --- a/tests/qtest/fuzz/fuzz.c +++ b/tests/qtest/fuzz/fuzz.c @@ -211,5 +211,8 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char ***envp) qemu_init(result.we_wordc, result.we_wordv, NULL); + /* re-enable the rcu atfork, which was previously disabled in qemu_init */ + rcu_enable_atfork(); + return 0; } -- 2.18.1