syzbot


WARNING in kvm_mmu_uninit_tdp_mmu

Status: fixed on 2022/03/08 16:11
Reported-by: syzbot+@syzkaller.appspotmail.com
Fix commit: 3a0f64de479c KVM: x86/mmu: Don't advance iterator after restart due to yielding
First crash: 230d, last: 147d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in kvm_mmu_uninit_tdp_mmu (2) C 10 61d 65d 0/22 upstream: reported C repro on 2022/04/23 10:56

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 5075 at arch/x86/kvm/mmu/tdp_mmu.c:46 kvm_mmu_uninit_tdp_mmu+0xb9/0xf0 arch/x86/kvm/mmu/tdp_mmu.c:46
Modules linked in:
CPU: 3 PID: 5075 Comm: syz-executor.0 Not tainted 5.17.0-rc2-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:kvm_mmu_uninit_tdp_mmu+0xb9/0xf0 arch/x86/kvm/mmu/tdp_mmu.c:46
Code: ea 03 80 3c 02 00 75 39 48 8b 83 d8 a0 00 00 48 39 c5 75 1a e8 08 e1 59 00 e8 e3 08 46 00 5b 5d e9 fc e0 59 00 e8 f7 e0 59 00 <0f> 0b eb b7 e8 ee e0 59 00 0f 0b eb dd e8 a5 9e a0 00 e9 60 ff ff
RSP: 0018:ffffc90021ac7d10 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc90021b79000 RCX: 0000000000000000
RDX: ffff88806927e140 RSI: ffffffff811dc409 RDI: 0000000000000003
RBP: ffffc90021b830e8 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff811dc390 R11: 0000000000000000 R12: ffffc90021b79000
R13: ffffc90021ac7d58 R14: 0000000000000003 R15: ffffc90021b7a240
FS:  0000555556370400(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555614d848 CR3: 000000006d353000 CR4: 0000000000152ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kvm_arch_destroy_vm+0x350/0x470 arch/x86/kvm/x86.c:11747
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1217 [inline]
 kvm_put_kvm+0x4fa/0xb00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1250
 kvm_vcpu_release+0x4d/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3668
 __fput+0x286/0x9f0 fs/file_table.c:311
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f70efa36c9b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007ffc5325cc40 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00007f70efa36c9b
RDX: 0000000000000000 RSI: 0000001b32928e98 RDI: 0000000000000005
RBP: 00007f70efb98960 R08: 0000000000000000 R09: 00000000babb5ae8
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000031099
R13: 00007ffc5325cd40 R14: 00007f70efb97030 R15: 0000000000000032
 </TASK>

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-qemu-upstream 2022/02/01 06:00 upstream 26291c54e111 6b7c57fe .config log report info WARNING in kvm_mmu_uninit_tdp_mmu
ci-qemu-upstream 2022/01/31 10:40 upstream 26291c54e111 a491ad2d .config log report info WARNING in kvm_mmu_uninit_tdp_mmu
ci-qemu-upstream 2021/11/10 06:13 upstream cb690f5238d7 55fa030c .config log report info WARNING in kvm_mmu_uninit_tdp_mmu