From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 12B1D15E8B; Sat, 27 Jun 2026 00:44:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782521087; cv=none; b=bvpETLJ+ZIhNM42fFvzRBLLUucRYtbcED0i4mLmnnYt78KLQIaYs7BNzkJLYLy26tj0Wse9Z1Jz7RPof5s+WEmupzn5DRSFr7qkdT7Q6thbut6TXp5BEpRD5WBIwMOvl3/a+rWgQGEdDK2sM6xNOlm7V0McawacgGeABm2+UiYQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782521087; c=relaxed/simple; bh=kUr2yPQCOsok+8rxx1oCI1yb2iBBXfSozLF9w97A8c8=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hTX909tjFYsIERs9vp56tMYLFNZy6zBvE+q6ShXPVZHxMBMBkvAsoBQHVmNjsO8YDFvupHO7oOZqefA2h1BIA63Keka0Aqa3CvEQZq1tOLLYRCp8sdXQzf7Ekt1KDi1aK6qBQm5nyoFMvOqI/04UFR1yQtQ18wgmQRwhUc6MQWw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P3IrGto/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="P3IrGto/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4E7291F00A3A; Sat, 27 Jun 2026 00:44:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782521086; bh=Xft+vbctEr1djAr+KskNxSck9zBs9troo/s4Ve2heuw=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=P3IrGto/ssl/6Aj0KV7T+Mcp2qpZPH2WtCGaQ498wYOm3HGEjWg/xQhVaFoYQHbl2 drAJyC+/0xpmPtQV77AMKRAMxKE0xRzY6JwrobJIpo5H3oXLcfu5W0HpWVC5XYB68O DaEvnkJ4umHKsLVLlrQp6vfuQTm4XrujoWigKhf7LI561Z1EXhd/3n9YV5qLTIkail r92R0mgaeJKYLM6iwdVNam3lnHAJu0n9i7IoVl5XTFba54xQIM1ZRsQTdq2LLtzT27 gqya1lJy5fQI+sGKvGfbdum8bbLUzCmQU7XKgREtqkJK1Zjra34tcddsQyXPuAvgKP fRZ0Ol0iJybRA== Date: Fri, 26 Jun 2026 17:44:45 -0700 From: Jakub Kicinski To: Simon Horman , lange_tang@163.com Cc: mst@redhat.com, xuanzhuo@linux.alibaba.com, jasowang@redhat.com, edumazet@google.com, virtualization@lists.linux.dev, netdev@vger.kernel.org, tanglongjun@kylinos.cn Subject: Re: [PATCH v4] virtio_net: disable cb when NAPI is busy-polled Message-ID: <20260626174445.700df7e3@kernel.org> In-Reply-To: <20260626151508.1319440-1-horms@kernel.org> References: <20260625013733.29300-1-lange_tang@163.com> <20260626151508.1319440-1-horms@kernel.org> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 26 Jun 2026 16:15:08 +0100 Simon Horman wrote: > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index 26afa6341d161..c1e252400c0fc 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -3011,6 +3011,8 @@ static int virtnet_poll(struct napi_struct *napi, int budget) > > unsigned int xdp_xmit = 0; > > bool napi_complete; > > > > + virtqueue_disable_cb(rq->vq); > > + > > [Severity: High] > Can this unconditionally disable the RX callback and cause a permanent network > stall when polled by netpoll? Good catch, Longjun just add if (budget)