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 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 2D928CAC598 for ; Tue, 16 Sep 2025 08:34:19 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uyR81-0005vl-6I; Tue, 16 Sep 2025 04:33:33 -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 1uyR7x-0005vA-Mj for qemu-devel@nongnu.org; Tue, 16 Sep 2025 04:33:30 -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 1uyR7s-0005vS-1p for qemu-devel@nongnu.org; Tue, 16 Sep 2025 04:33:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1758011601; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=vvTDlb4UjeARLk7ny3NZlaug8tFqjjbSEOcKnmUpme4=; b=h/8dpUQF6hYr6x04s0UBx1FMIRkUdF5F6Wtho2RphlWy1SJvIzorDBwEXC8oImPgsD5ZmX Zd5Nv7z0c7/DKKlzWB70U7P6SDK1W7oeayZy8MdIycfhELui1facRoB89xn4rM5zt6U3fK ZcbBt4ef9UrAgixDsDtsXDHcHxb+ZUM= Received: from mx-prod-mc-06.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-74-zPqhcYPcOkqMAs4ZZkoqMQ-1; Tue, 16 Sep 2025 04:33:18 -0400 X-MC-Unique: zPqhcYPcOkqMAs4ZZkoqMQ-1 X-Mimecast-MFC-AGG-ID: zPqhcYPcOkqMAs4ZZkoqMQ_1758011596 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-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C0C0A18005A5; Tue, 16 Sep 2025 08:33:15 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.153]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8DCD11800579; Tue, 16 Sep 2025 08:33:10 +0000 (UTC) Date: Tue, 16 Sep 2025 09:33:06 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Vladimir Sementsov-Ogievskiy Cc: qemu-devel@nongnu.org, peterx@redhat.com, qemu-block@nongnu.org, leiyang@redhat.com, marcandre.lureau@redhat.com, "Michael S. Tsirkin" , Stefano Garzarella , Jason Wang , Michael Roth , Kostiantyn Kostiuk , Paolo Bonzini , Stefan Weil , Coiby Xu Subject: Re: [PATCH v4 06/12] util: drop qemu_socket_set_nonblock() Message-ID: References: <20250915193105.230085-1-vsementsov@yandex-team.ru> <20250915193105.230085-7-vsementsov@yandex-team.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250915193105.230085-7-vsementsov@yandex-team.ru> User-Agent: Mutt/2.2.14 (2025-02-20) 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: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.035, 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_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_PASS=-0.001, T_SPF_HELO_TEMPERROR=0.01 autolearn=unavailable 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Sep 15, 2025 at 10:30:58PM +0300, Vladimir Sementsov-Ogievskiy wrote: > Use common qemu_set_blocking() instead. > > Note that pre-patch the behavior of Win32 and Linux realizations > are inconsistent: we ignore failure for Win32, and assert success > for Linux. > > How do we convert the callers? > > 1. Most of callers call qemu_socket_set_nonblock() on a > freshly created socket fd, in conditions when we may simply > report an error. Seems correct switching to error handling > both for Windows (pre-patch error is ignored) and Linux > (pre-patch we assert success). Anyway, we normally don't > expect errors in these cases. > > Still in tests let's use &error_abort for simplicity. > > What are exclusions? > > 2. hw/virtio/vhost-user.c - we are inside #ifdef CONFIG_LINUX, > so no damage in switching to error handling from assertion. > > 3. io/channel-socket.c: here we convert both old calls to > qemu_socket_set_nonblock() and qemu_socket_set_block() to > one new call. Pre-patch we assert success for Linux in > qemu_socket_set_nonblock(), and ignore all other errors here. > So, for Windows switch is a bit dangerous: we may get > new errors or crashes(when error_abort is passed) in > cases where we have silently ignored the error before > (was it correct in all such cases, if they were?) Still, > there is no other way to stricter API than take > this risk. > > 4. util/vhost-user-server - compiled only for Linux (see > util/meson.build), so we are safe, switching from assertion to > &error_abort. > > Note: In qga/channel-posix.c we use g_warning(), where g_printerr() > would actually be a better choice. Still let's for now follow > common style of qga, where g_warning() is commonly used to print > such messages, and no call to g_printerr(). Converting everything > to use g_printerr() should better be another series. > > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > contrib/ivshmem-server/ivshmem-server.c | 9 ++++++++- > hw/hyperv/syndbg.c | 4 +++- > hw/virtio/vhost-user.c | 5 ++++- > include/qemu/sockets.h | 1 - > io/channel-socket.c | 7 +++---- > net/dgram.c | 16 +++++++++++++--- > net/l2tpv3.c | 5 +++-- > net/socket.c | 20 ++++++++++++++++---- > qga/channel-posix.c | 7 ++++++- > tests/unit/socket-helpers.c | 4 +++- > tests/unit/test-crypto-tlssession.c | 8 ++++---- > util/oslib-posix.c | 7 ------- > util/oslib-win32.c | 5 ----- > util/vhost-user-server.c | 4 ++-- > 14 files changed, 65 insertions(+), 37 deletions(-) > diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c > index d805a92394..b3416ab956 100644 > --- a/util/vhost-user-server.c > +++ b/util/vhost-user-server.c > @@ -78,7 +78,7 @@ static void vmsg_unblock_fds(VhostUserMsg *vmsg) > } > > for (i = 0; i < vmsg->fd_num; i++) { > - qemu_socket_set_nonblock(vmsg->fds[i]); > + qemu_set_blocking(vmsg->fds[i], false, &error_abort); > } > } The caller of this method is able to handle errors more gracefully than abort. > @@ -303,7 +303,7 @@ set_watch(VuDev *vu_dev, int fd, int vu_evt, > > vu_fd_watch->fd = fd; > vu_fd_watch->cb = cb; > - qemu_socket_set_nonblock(fd); > + qemu_set_blocking(fd, false, &error_abort); > aio_set_fd_handler(server->ctx, fd, kick_handler, > NULL, NULL, NULL, vu_fd_watch); > vu_fd_watch->vu_dev = vu_dev; Can we put a TODO here that error_abort should be fixed to be more graceful - either by moving the set_blocking call out of this callback entirely, or allowing this method to return errors. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|