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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61093C83F12 for ; Mon, 28 Aug 2023 15:24:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230501AbjH1PYE convert rfc822-to-8bit (ORCPT ); Mon, 28 Aug 2023 11:24:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54920 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229719AbjH1PXc (ORCPT ); Mon, 28 Aug 2023 11:23:32 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B68CCE0; Mon, 28 Aug 2023 08:23:30 -0700 (PDT) Received: from hamburger.collabora.co.uk (hamburger.collabora.co.uk [IPv6:2a01:4f8:1c1c:f269::1]) by madras.collabora.co.uk (Postfix) with ESMTP id A774A660716E; Mon, 28 Aug 2023 16:23:26 +0100 (BST) From: "Muhammad Usama Anjum" In-Reply-To: Content-Type: text/plain; charset="utf-8" X-Forward: 127.0.0.1 Date: Mon, 28 Aug 2023 16:23:26 +0100 Cc: "syzbot" , syzkaller-lts-bugs@googlegroups.com, "syzbot" , "Paolo Bonzini" , "Vitaly Kuznetsov" , "Wanpeng Li" , "Jim Mattson" , "Joerg Roedel" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , =?utf-8?q?H=2E_Peter_Anvin?= , "Jarkko Sakkinen" , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org To: "Sean Christopherson" MIME-Version: 1.0 Message-ID: <6ba2-64ecbc00-5-39397d40@6469447> Subject: =?utf-8?q?Re=3A?==?utf-8?q?_[v5=2E15]?= WARNING in =?utf-8?q?kvm=5Farch=5Fvcpu=5Fioctl=5Frun?= User-Agent: SOGoMail 5.8.4 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Monday, August 28, 2023 08:11 PM PKT, Sean Christopherson wrote: > On Mon, Aug 28, 2023, Muhammad Usama Anjum wrote: > > On 5/5/23 1:28 PM, syzbot wrote: > > > syzbot has found a reproducer for the following issue on: > > > > > > HEAD commit: 8a7f2a5c5aa1 Linux 5.15.110 > > This same warning has also been found on 6.1.21. > > > > > git tree: linux-5.15.y > > > console output: https://syzkaller.appspot.com/x/log.txt?x=15f12318280000 > > > kernel config: https://syzkaller.appspot.com/x/.config?x=ba8d5c9d6c5289f > > > dashboard link: https://syzkaller.appspot.com/bug?extid=412c9ae97b4338c5187e > > > compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 > > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10e13c84280000 > > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=149d9470280000 > > I've tried all the C and syz reproducers. I've also tried syz-crash which > > launched multiple instances of VMs and ran syz reproducer. But the issue > > didn't get reproduced. > > > > I don't have kvm skills. Can someone have a look at the the warning > > (probably by static analysis)? > > > > > > > > Downloadable assets: > > > disk image: https://storage.googleapis.com/syzbot-assets/fc04f54c047f/disk-8a7f2a5c.raw.xz > > > vmlinux: https://storage.googleapis.com/syzbot-assets/6b4ba4cb1191/vmlinux-8a7f2a5c.xz > > > kernel image: https://storage.googleapis.com/syzbot-assets/d927dc3f9670/bzImage-8a7f2a5c.xz > > > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > > Reported-by: syzbot+412c9ae97b4338c5187e@syzkaller.appspotmail.com > > > > > > ------------[ cut here ]------------ > > > WARNING: CPU: 0 PID: 3502 at arch/x86/kvm/x86.c:10310 kvm_arch_vcpu_ioctl_run+0x1d63/0x1f80 > > "Fixed" by https://lore.kernel.org/all/20230808232057.2498287-1-seanjc@google.com, > in quotes because sadly the fix was to simply delete the sanity check :-( Thank you so much Sean. Thank you so much Sean. Syzbot has been finding the issue in LTS kernels. I'm not sure if we should backport a patch which is just removing a false warning. #syz fix: KVM: x86: Remove WARN sanity check on hypervisor timer vs. UNINITIALIZED vCPU