From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794502415; b=g26tAzPJgeZirBHd5YvMz5URodLJnTblKf01vZ+TQNnf6LMIUbBJ1360IS+j0NWvBHCO 2CZ8xqYeDyYzh+nwWqHsuZF1QS36+zqbOl5ThaN8AXhiOxIrsqRVPwluEhMV7LdoQcr8Z uvmGxFGim7ZlkxWZ8NIDQh2TPt6NZ4T9PgYxDBWCOkBsYevF/r136cKpbzbzJBDFvoy63 si0aS5J154HZoAvtuCXIM5Arb/HsPaoMM9hSpnq8kCBhc2VIUAk5CllVjr/DP+CNbSHsg eQGhd1wCYc9UD68QnNYQ06C7liO0hd5cCllHs7ajVIdhMbU92J9fhgEVFq8VE3f+yDw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794502415; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: In-Reply-To:References:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=kUesCCpeSihhizE+ryMsGam5gkt2oL/j/Joc00r5DNc=; b=sgny033oZaNrA1zTts28EkXGJwiMUJYdQmwCQ8cNJB0faVv8JNey2Xms5WGSpzu7d1ln K8VXz0yzK7y/G6OSh6riwSo1RGOg1cCJF4tN4go5Ji12hktwfAo2XAto/3/BpAsMxUGdw MOwS1JO4WPhe69IKEPq12ywdmSGJZd/jKBAdboqNOPf8glojeu5CVfMztk/bSl2XQpop7 XF+x8P2ieZXv5pE+NftDJZeCwNqi01VJ8a2z90gRnonD8YkLDuIO8uzE1Q6xiwb1GDwbj iRZvX/I/SrPSYLV2YLOwXw1HlPK/Kpd47hza4l/7A+1GF9frSGi/yHfEPd/+2OuVSuw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ML4tXTMR; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 29952606A31C; Thu, 12 Nov 2026 16:53:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ML4tXTMR Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7414B1F000C4; Thu, 12 Nov 2026 16:53:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794502414; bh=kUesCCpeSihhizE+ryMsGam5gkt2oL/j/Joc00r5DNc=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=ML4tXTMRuQPNOPSoszh5R0pfwKAhIx5zHlg1LhoCuK5VA7sv2nSyM6gl6oSeGtuHt DBl2xctqAu+tua6sz/sBZjw4RTAmeaQdZxruL6Acisc5Ly/MEgcpEu5D+g3YK5+Sps ozh7BpDB4CZQrm9qSMlLS1q2vhuzTSvaQpUMhiaHkPKYkpthffJ0TVMcKFgidEJwWI aKOB5Z/i8fE9sZyDiw2w3wJTlthfkHLC+tlnkzEmzmu7QzdHz68DWxxEpmi/YDb+nZ XQJJ5yzwqffB9XdzeldfRAKT5sR65dTTSV0k19rff0u2tr7NVzRbmZc9nLqJnRQkxQ dsLqWX/+HMpXw== Date: Thu, 12 Nov 2026 08:53:33 -0800 From: Jakub Kicinski To: Longjun Tang Cc: mst@redhat.com, eperezma@redhat.com, jasowangio@gmail.com, xuanzhuo@linux.alibaba.com, virtualization@lists.linux.dev, netdev@vger.kernel.org, tanglongjun@kylinos.cn Subject: Re: [PATCH 2/3] virtio_net: introduce an RX queue watchdog for stuck detection Message-ID: <20261112085333.77476864@kernel.org> In-Reply-To: <20261109094310.103979-3-lange_tang@163.com> References: <20261109094310.103979-1-lange_tang@163.com> <20261109094310.103979-3-lange_tang@163.com> X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 9 Nov 2026 17:43:09 +0800 Longjun Tang wrote: > The backend raises an interrupt after adding buffers to the used ring, > and the hypervisor injects it. If one is lost (e.g., a transient KVM > failure), NAPI will not be scheduled and the driver stops consuming > buffers. The ring eventually fills up, the backend stops notifying, and > the queue is left permanently stuck. Can you say more about what platform you're hitting this problem on? An what's the virtio backend?