syzbot


WARNING: locking bug in __timer_delete_sync

Status: upstream: reported on 2024/06/01 15:52
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+0ece6edfd05ed20e32d9@syzkaller.appspotmail.com
Fix commit: b79922009214 bcachefs: Add missing synchronize_srcu_expedited() call when shutting down
Patched on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-linux-next-kasan-gce-root ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-net-next-test-gce ci2-upstream-usb], missing on: [ci-qemu-native-arm64-kvm ci-qemu2-riscv64 ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-net-kasan-gce]
First crash: 20d, last: 1d02h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bcachefs?] WARNING: locking bug in __timer_delete_sync 0 (1) 2024/06/01 15:52

Sample crash report:
------------[ cut here ]------------
Looking for class "dp->delay_work)" with key __key.4, but found a different class "(&sdp->delay_work)" with the same key
WARNING: CPU: 0 PID: 7767 at kernel/locking/lockdep.c:932 look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Modules linked in:
CPU: 0 PID: 7767 Comm: syz-executor.1 Not tainted 6.10.0-rc3-syzkaller-00044-g2ccbdf43d5e7 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:look_up_lock_class+0x133/0x140 kernel/locking/lockdep.c:932
Code: c7 c7 20 b9 2c 8b e8 cc 53 74 f6 90 0f 0b 90 90 90 31 db eb be c6 05 f5 86 ef 04 01 90 48 c7 c7 40 bc 2c 8b e8 ae 53 74 f6 90 <0f> 0b 90 90 e9 62 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90007e4fa38 EFLAGS: 00010086
RAX: 0000000000000000 RBX: ffffffff9426b6b0 RCX: ffffffff81511289
RDX: ffff88801f91a440 RSI: ffffffff81511296 RDI: 0000000000000001
RBP: ffffffff94ad9ac0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 20676e696b6f6f4c R12: ffffe8ffad07e578
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff94ad8be0
FS:  0000000000000000(0000) GS:ffff88802c000000(0063) knlGS:0000000056967400
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000c001a09000 CR3: 0000000024f96000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 register_lock_class+0xb1/0x1230 kernel/locking/lockdep.c:1284
 __lock_acquire+0x111/0x3b30 kernel/locking/lockdep.c:5014
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 __timer_delete_sync+0x152/0x1b0 kernel/time/timer.c:1647
 del_timer_sync include/linux/timer.h:185 [inline]
 cleanup_srcu_struct+0x124/0x520 kernel/rcu/srcutree.c:659
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1351 [inline]
 kvm_put_kvm+0x8df/0xb80 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1380
 kvm_vm_release+0x42/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1403
 __fput+0x408/0xbb0 fs/file_table.c:422
 __fput_sync+0x47/0x50 fs/file_table.c:507
 __do_sys_close fs/open.c:1555 [inline]
 __se_sys_close fs/open.c:1540 [inline]
 __ia32_sys_close+0x86/0x100 fs/open.c:1540
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf72d9579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000ffc9ea20 EFLAGS: 00000293 ORIG_RAX: 0000000000000006
RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000056967400
RDX: 0000000000000000 RSI: 00000000f742fff4 RDI: 00000000ffffffff
RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/17 09:20 upstream 2ccbdf43d5e7 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING: locking bug in __timer_delete_sync
2024/06/15 12:37 upstream 2ccbdf43d5e7 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING: locking bug in __timer_delete_sync
2024/05/28 15:48 upstream 2bfcfd584ff5 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING: locking bug in __timer_delete_sync
* Struck through repros no longer work on HEAD.