From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 9E1BE2FF16D for ; Fri, 15 Aug 2025 10:44:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755254697; cv=none; b=ojqPfX5qVWIE5dILcEtdI8M5BUZSIQGf1q0V6e55lwGSO/rldyRdQjXPEmhS8dMWtC1YolBc6RZwC55wlGWR1Y1b7MB8uESV5APYOyLGdMTtqDjaIAF5QJ9eMSHK6ppL6YL0CCWNMOKsSPwm0Bq71LT63rwr4LOafu9McrT825I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755254697; c=relaxed/simple; bh=WjR/rbwNJc0Qp2k2aQAdE2Gr22tCrag3f7ATcKE39Uc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ueFpxfB6nu5BNENIzo7Q0MtvLZp44H+Sc1Iw+csW+qOnFRvcAcPCYQxTztDS5iIUB5wXMwFxzJqV734Yg1LGk+bx4PeZTdAxuYlVnzVqbRP+Hxd00dDlTcimG94qaokryALrvY2DkMV9FA7QcqUPvnThaFUD9nS7FMyjxO1u0+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=D3RvSpFi; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="D3RvSpFi" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755254694; 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: in-reply-to:in-reply-to:references:references; bh=V5GOAcmmdxLGbEbM9B2YGjZnwu9h8dtTUkFqo/i0QYA=; b=D3RvSpFiPsa2FmJK2sfh5ZvZRlyGaew1zKj73nGe2fS1qiPQzYiRg6FIyd+aDiwS8hK6w3 T+IKNXAPb2MbEv8ZMbejg1gflqnjIqvne/zCNWDPoZJPOmc8w+0Zj099Z98PcHgTFBq/d5 HHK87JjrXRJ6v00iqcOmSPMpfmJ6b9Q= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-213-KxvZ1i8aNyicUvDI3i05iA-1; Fri, 15 Aug 2025 06:44:53 -0400 X-MC-Unique: KxvZ1i8aNyicUvDI3i05iA-1 X-Mimecast-MFC-AGG-ID: KxvZ1i8aNyicUvDI3i05iA_1755254692 Received: by mail-wr1-f72.google.com with SMTP id ffacd0b85a97d-3b9e41037e6so847665f8f.1 for ; Fri, 15 Aug 2025 03:44:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755254692; x=1755859492; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=V5GOAcmmdxLGbEbM9B2YGjZnwu9h8dtTUkFqo/i0QYA=; b=UiCczzI5YT0CId9GDx6eb/D0ZrH9ydnlfNH1McRXz2xRUS3LOHHk5dPCc/87DCuIb6 wrgR8sYAkko3lkVJ8szN8uyoY0InQU/jYNsdl8AoW32NmaUfGSYlglksO2uQHrEfEBbj Nqqo0B+fS5st+KyjwSyAuxJTBU1iUnFZ6ZmF8YQ8VZ5R+5yaVjaRqp7IaoljREsJ7d3o cAPhQwdPAX+GZTlBZS5sr8xeVqGHGjVS6+RxTV9yL0kiSO2wuPNsLxTYcEisBIS3OkWH IUo9NYL5/aV8edo7LfNG6zwq3pO9OXov/F4sDuTcmo7DhaQzIuBYCFF7bCZ1K6yKH3qF 4NNA== X-Forwarded-Encrypted: i=1; AJvYcCVOf3lH51i5QNslQCSy6e9goiDINdAfzhoOJRpD7lm90fpp7NufCyRCkjlzmCSgqkCZh1Q=@vger.kernel.org X-Gm-Message-State: AOJu0YzlTJl2c/+DPtkKaks8tw9K3l6k+iJ7M3al6fTN1dult3I4vCO0 39UVOjwGaLWAW0fKbL8fyinIxy33cie6LxRMRG4cvp3wHpVu+yG7X2M0BBZrW3dQjTxyH1k02Yy aXEY0mjyFp3UEyTezkqbxpAkYe4Q8afY0gfoWAnPKEb1L71UNRyH+nA== X-Gm-Gg: ASbGnctnn6FHBAR7esQ1L62dKcg6yIIX9zLl+uuWOMTVx0ZErz+BrihQYUDYA3FABtM o99Yov6sR/IBVyvcT+w1I/UOmhozrAL9nY6H54f1feY2KRcDfWQ6bxJKvpJgT/RkzAHbWxgjaBy 9lmdaaSyZQnI3lMHvWVV/QdzYFQEl5X8IA3VbDck5wJA7u+Rqn0AdC23xhYCCZV7QoihwUFhzhD zyjNfqX5s5CzDD567HW6VXSmIR6Lwam120rA0Ru1MbKaIcsXoMXivs0fxw+FZSWpcJE2IraVXMn 92+DeINESMlwS9x0B+e0zDYioV7wbRA6knI= X-Received: by 2002:a05:6000:1a8d:b0:3b7:9d83:50ef with SMTP id ffacd0b85a97d-3bb694af396mr1111608f8f.55.1755254691697; Fri, 15 Aug 2025 03:44:51 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFjxJ9VfnonVDFqga9qmU4sokEZCEtKZYfi4E6SPLLakFaeJSs6iOf6aXLBGPZEAaqLwiSlKQ== X-Received: by 2002:a05:6000:1a8d:b0:3b7:9d83:50ef with SMTP id ffacd0b85a97d-3bb694af396mr1111588f8f.55.1755254691299; Fri, 15 Aug 2025 03:44:51 -0700 (PDT) Received: from redhat.com ([2a06:c701:73cf:b700:6c5c:d9e7:553f:9f71]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3bb676c9936sm1456218f8f.38.2025.08.15.03.44.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Aug 2025 03:44:50 -0700 (PDT) Date: Fri, 15 Aug 2025 06:44:47 -0400 From: "Michael S. Tsirkin" To: Will Deacon Cc: syzbot , davem@davemloft.net, edumazet@google.com, eperezma@redhat.com, horms@kernel.org, jasowang@redhat.com, kuba@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, sgarzare@redhat.com, stefanha@redhat.com, syzkaller-bugs@googlegroups.com, virtualization@lists.linux.dev, xuanzhuo@linux.alibaba.com Subject: Re: [syzbot] [kvm?] [net?] [virt?] WARNING in virtio_transport_send_pkt_info Message-ID: <20250815063140-mutt-send-email-mst@kernel.org> References: <20250812052645-mutt-send-email-mst@kernel.org> <689b1156.050a0220.7f033.011c.GAE@google.com> <20250812061425-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Aug 15, 2025 at 11:09:24AM +0100, Will Deacon wrote: > On Tue, Aug 12, 2025 at 06:15:46AM -0400, Michael S. Tsirkin wrote: > > On Tue, Aug 12, 2025 at 03:03:02AM -0700, syzbot wrote: > > > Hello, > > > > > > syzbot has tested the proposed patch but the reproducer is still triggering an issue: > > > WARNING in virtio_transport_send_pkt_info > > > > OK so the issue triggers on > > commit 6693731487a8145a9b039bc983d77edc47693855 > > Author: Will Deacon > > Date: Thu Jul 17 10:01:16 2025 +0100 > > > > vsock/virtio: Allocate nonlinear SKBs for handling large transmit buffers > > > > > > but does not trigger on: > > > > commit 8ca76151d2c8219edea82f1925a2a25907ff6a9d > > Author: Will Deacon > > Date: Thu Jul 17 10:01:15 2025 +0100 > > > > vsock/virtio: Rename virtio_vsock_skb_rx_put() > > > > > > > > Will, I suspect your patch merely uncovers a latent bug > > in zero copy handling elsewhere. > > Want to take a look? > > Sorry for the delay, I was debugging something else! > > I see Hillf already tried some stuff in the other thread, but I can take > a look as well. > > Will I will be frank I don't understand how that patch makes sense though. -- MST