[syzbot] [kvm?] WARNING in __kvm_gpc_refresh

syzbot
2024-03-18T16:25:31Z

Hello,

syzbot found the following issue on:

HEAD commit: 277100b3d5fe Merge tag 'block-6.9-20240315' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17c96aa5180000
kernel config: https://syzkaller.appspot.com/x/.config?x=1c6662240382da2
dashboard link: https://syzkaller.appspot.com/bug?extid=106a4f72b0474e1d1b33
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14358231180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110ed231180000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-277100b3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6872e049b27c/vmlinux-277100b3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/68ec7230df0f/bzImage-277100b3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+106a4f72b0474e1d1b33@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5192 at arch/x86/kvm/../../../virt/kvm/pfncache.c:247 __kvm_gpc_refresh+0x15e2/0x2200 arch/x86/kvm/../../../virt/kvm/pfncache.c:247
Modules linked in:
CPU: 1 PID: 5192 Comm: syz-executor422 Not tainted 6.8.0-syzkaller-11063-g277100b3d5fe #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__kvm_gpc_refresh+0x15e2/0x2200 arch/x86/kvm/../../../virt/kvm/pfncache.c:247
Code: 48 c7 c2 a0 5e 02 8b be 5d 03 00 00 48 c7 c7 60 5e 02 8b c6 05 bd 89 7c 0e 01 e8 a9 23 5e 00 e9 31 fb ff ff e8 5f 85 80 00 90 <0f> 0b 90 e9 69 f7 ff ff e8 51 85 80 00 48 8b 54 24 40 48 b8 00 00
RSP: 0018:ffffc9000317f940 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffffffff810c86ad
RDX: ffff888022360000 RSI: ffffffff810c9c31 RDI: 0000000000000000
RBP: ffff88802f2c0948 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000002 R12: ffff888000000000
R13: ffff887fffffff01 R14: 0000000000000020 R15: 0000000000000001
FS: 000055555b2d9380(0000) GS:ffff88806b300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000002fa8a000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
kvm_gpc_refresh+0x7d/0xe0 arch/x86/kvm/../../../virt/kvm/pfncache.c:364
kvm_setup_guest_pvclock+0x5b/0x6f0 arch/x86/kvm/x86.c:3174
kvm_guest_time_update+0x935/0xeb0 arch/x86/kvm/x86.c:3313
vcpu_enter_guest arch/x86/kvm/x86.c:10769 [inline]
vcpu_run+0x1993/0x4e60 arch/x86/kvm/x86.c:11211
kvm_arch_vcpu_ioctl_run+0x42e/0x1680 arch/x86/kvm/x86.c:11437
kvm_vcpu_ioctl+0x5a1/0x1060 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4464
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl fs/ioctl.c:890 [inline]
__x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fb4618fd069
Code: 48 83 c4 28 c3 e8 d7 19 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd71e140e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb4618fd069 RCX: 00007fb4618fd069
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007fb46194a07e R08: 00007ffd71e14218 R09: 00007ffd71e14218
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd71e14150
R13: 00007ffd71e14130 R14: 00007ffd71e14120 R15: 00007fb46194a012
</TASK>

---
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