On Monday, August 28, 2023 08:11 PM PKT, Sean Christopherson <seanjc@xxxxxxxxxx> 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@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > > > ------------[ 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@xxxxxxxxxx, > 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
