From patchwork Fri Sep 8 12:26:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 13377417 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 64D1BEE7FE4 for ; Fri, 8 Sep 2023 12:28:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qeab8-0006rn-Fn; Fri, 08 Sep 2023 08:28:30 -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 1qeaax-0006mK-KU for qemu-devel@nongnu.org; Fri, 08 Sep 2023 08:28:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qeaat-00087V-HV for qemu-devel@nongnu.org; Fri, 08 Sep 2023 08:28:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694176093; 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=/EZLGQdvr5+VhP6LPPuCDM+vLcYqtKWyHCeVVYuju1Y=; b=DVzm0DEG9V9gPCWL+KJgGHd5cPhbXdsdYOu/heX1VJMTF5YVnkqnVul54/u9JFlV9VeX+l CVXoRtoyv4cGA2AMfrPQuZg0ci6jlLZy6NgTcPUtsTcC6ZtFk8KpxwpNg+iyGXc8mHKtr3 rQrKgGPNbXlm1kGg3V0yJcuNno7lN60= 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-497-yikZQkeSMru92-xkxufN3w-1; Fri, 08 Sep 2023 08:28:10 -0400 X-MC-Unique: yikZQkeSMru92-xkxufN3w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C62559464C1; Fri, 8 Sep 2023 12:28:09 +0000 (UTC) Received: from green.redhat.com (unknown [10.2.16.21]) by smtp.corp.redhat.com (Postfix) with ESMTP id F3CA41460FE5; Fri, 8 Sep 2023 12:28:08 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Cc: "Denis V. Lunev" , Kevin Wolf , Vladimir Sementsov-Ogievskiy , Hanna Reitz , Mike Maslenkin , qemu-block@nongnu.org (open list:Network Block Dev...) Subject: [PULL v2 12/13] qemu-nbd: Restore "qemu-nbd -v --fork" output Date: Fri, 8 Sep 2023 07:26:38 -0500 Message-ID: <20230908122625.1031340-27-eblake@redhat.com> In-Reply-To: <20230908122625.1031340-15-eblake@redhat.com> References: <20230908122625.1031340-15-eblake@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eblake@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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: "Denis V. Lunev" Closing stderr earlier is good for daemonized qemu-nbd under ssh earlier, but breaks the case where -v is being used to track what is happening in the server, as in iotest 233. When we know we are verbose, we should preserve original stderr and restore it once the setup stage is done. This commit restores the original behavior with -v option. In this case original output inside the test is kept intact. Reported-by: Kevin Wolf Signed-off-by: Denis V. Lunev CC: Eric Blake CC: Vladimir Sementsov-Ogievskiy CC: Hanna Reitz CC: Mike Maslenkin Fixes: 5c56dd27a2 ("qemu-nbd: fix regression with qemu-nbd --fork run over ssh") Message-ID: <20230906093210.339585-7-den@openvz.org> Reviewed-by: Eric Blake Tested-by: Eric Blake [eblake: fix build by avoiding stderr as struct member name] Signed-off-by: Eric Blake --- qemu-nbd.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/qemu-nbd.c b/qemu-nbd.c index 7c4e22def17..30eeb6f3c75 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -255,18 +255,23 @@ struct NbdClientOpts { char *device; char *srcpath; SocketAddress *saddr; + int old_stderr; bool fork_process; bool verbose; }; -static void nbd_client_release_pipe(void) +static void nbd_client_release_pipe(int old_stderr) { /* Close stderr so that the qemu-nbd process exits. */ - if (dup2(STDOUT_FILENO, STDERR_FILENO) < 0) { + if (dup2(old_stderr, STDERR_FILENO) < 0) { error_report("Could not release pipe to parent: %s", strerror(errno)); exit(EXIT_FAILURE); } + if (old_stderr != STDOUT_FILENO && close(old_stderr) < 0) { + error_report("Could not release qemu-nbd: %s", strerror(errno)); + exit(EXIT_FAILURE); + } } #if HAVE_NBD_DEVICE @@ -332,7 +337,7 @@ static void *nbd_client_thread(void *arg) fprintf(stderr, "NBD device %s is now connected to %s\n", opts->device, opts->srcpath); } else { - nbd_client_release_pipe(); + nbd_client_release_pipe(opts->old_stderr); } if (nbd_client(fd) < 0) { @@ -597,6 +602,7 @@ int main(int argc, char **argv) .device = NULL, .srcpath = NULL, .saddr = NULL, + .old_stderr = STDOUT_FILENO, }; #ifdef CONFIG_POSIX @@ -951,6 +957,16 @@ int main(int argc, char **argv) close(stderr_fd[0]); + /* Remember parent's stderr if we will be restoring it. */ + if (opts.verbose /* fork_process is set */) { + opts.old_stderr = dup(STDERR_FILENO); + if (opts.old_stderr < 0) { + error_report("Could not dup original stderr: %s", + strerror(errno)); + exit(EXIT_FAILURE); + } + } + ret = qemu_daemon(1, 0); saved_errno = errno; /* dup2 will overwrite error below */ @@ -1181,7 +1197,7 @@ int main(int argc, char **argv) } if (opts.fork_process) { - nbd_client_release_pipe(); + nbd_client_release_pipe(opts.old_stderr); } state = RUNNING;