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 E6BD1C369CB for ; Wed, 23 Apr 2025 12:59:38 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u7Zh5-00088K-SE; Wed, 23 Apr 2025 08:59:15 -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 1u7Zh2-00087M-HM for qemu-devel@nongnu.org; Wed, 23 Apr 2025 08:59:12 -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 1u7Zh0-0006g0-ON for qemu-devel@nongnu.org; Wed, 23 Apr 2025 08:59:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1745413149; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ip6nIepuR3CPYP6YxFv0L5w8gHprusaVkUoVUB2lS40=; b=EFU7CdwJd4yrpWY0Fywkb9XJBLK+vFjLfaK9KoQorzGNdPaFgy+DlO+mmClP3NiyRpObyr dHjG6cAceCdksrC7zWnubwu5+kOXQfincR0Jgq+sfrTwprfc8EtkPP3arRSEF7sec/hT3m sn+Zq6PMw5YnXGUuTMBqbksXKxWcU60= Received: from mx-prod-mc-08.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-177-3ePjp1zhOT2ZzLmrjc1o6w-1; Wed, 23 Apr 2025 08:59:07 -0400 X-MC-Unique: 3ePjp1zhOT2ZzLmrjc1o6w-1 X-Mimecast-MFC-AGG-ID: 3ePjp1zhOT2ZzLmrjc1o6w_1745413145 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-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 43D651800EC9; Wed, 23 Apr 2025 12:59:05 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.34]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8CE271800352; Wed, 23 Apr 2025 12:59:02 +0000 (UTC) Date: Wed, 23 Apr 2025 13:58:57 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Dietmar Maurer Cc: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , qemu-devel@nongnu.org Subject: Re: [PATCH v3 9/9] h264: register shutdown notifiers, stop pipeline in destroy_encoder_context Message-ID: References: <20250418112953.1744442-1-dietmar@proxmox.com> <20250418112953.1744442-10-dietmar@proxmox.com> <300596504.3803.1745303752280@webmail.proxmox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <300596504.3803.1745303752280@webmail.proxmox.com> 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=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.294, 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_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: , 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 Tue, Apr 22, 2025 at 08:35:52AM +0200, Dietmar Maurer wrote: > > On Fri, Apr 18, 2025 at 3:30 PM Dietmar Maurer wrote: > > > > > > Some encoders can hang indefinetly (i.e. nvh264enc) if > > > > indefinitely > > > > > the pipeline is not stopped before it is destroyed > > > (Observed on Debian bookworm). > > > > but why do you need the extra shutdown notifier? > > Because Qemu does not close open VNC connections on shutdown. > and if the VNC connection is open, the h264 pipeline is still active, > which cause the Qemu process to hang (CTRL-C does not stop it, only kill -9) This is surely liable to be a race condition that causes crashes. The still open VNC connection may still reference the encoder that you're destroying, allowing the VNC worker thread to potentially access free'd memory. 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 :|