general protection fault in debug_check_no_obj_freed (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 69d5b97c5973 HID: we do not randomly make new drivers 'def..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10814183400000
kernel config: https://syzkaller.appspot.com/x/.config?x=5c0a49d2b5210087
dashboard link: https://syzkaller.appspot.com/bug?extid=847c47c2467d2be77f12
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [ak...@linux-foundation.org arya...@virtuozzo.com
gu...@fb.com han...@cmpxchg.org jba...@fb.com ktk...@virtuozzo.com
linux-...@vger.kernel.org linu...@kvack.org mho...@suse.com
penguin...@I-love.SAKURA.ne.jp shak...@google.com]

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+847c47...@syzkaller.appspotmail.com

bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7191 Comm: syz-executor0 Not tainted 4.19.0+ #84
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:778 [inline]
RIP: 0010:debug_check_no_obj_freed+0x1bb/0x58d lib/debugobjects.c:818
Code: 48 8b b5 48 ff ff ff 48 c7 c0 60 fe f9 8a 4c 8b 2c 30 4d 85 ed 0f 84
87 02 00 00 31 f6 4d 89 e7 41 89 f4 4c 89 e8 48 c1 e8 03 <42> 80 3c 30 00
0f 85 91 02 00 00 49 8d 7d 18 41 83 c4 01 49 8b 5d
RSP: 0018:ffff8801bca7b148 EFLAGS: 00010006
RAX: 0407040646640706 RBX: 2038203233203833 RCX: 0000000000000001
RDX: 3320382030363120 RSI: 0000000000000000 RDI: ffffffff890113b0
RBP: ffff8801bca7b238 R08: ffffed003794f616 R09: ffffed003794f615
R10: ffffed003794f615 R11: 0000000000000003 R12: 0000000000000004
R13: 2038203233203833 R14: dffffc0000000000 R15: ffffffff8b030c68
FS: 00007f48a7454700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 0000000160d3f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
free_pages_prepare mm/page_alloc.c:1035 [inline]
free_pcp_prepare mm/page_alloc.c:1049 [inline]
free_unref_page_prepare mm/page_alloc.c:2744 [inline]
free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2813
shrink_page_list+0x6dc3/0xccd0 mm/vmscan.c:1501
shrink_inactive_list+0x77b/0x1c60 mm/vmscan.c:1963
shrink_list mm/vmscan.c:2275 [inline]
shrink_node_memcg+0x78b/0x18f0 mm/vmscan.c:2540
shrink_node+0x3bc/0x16b0 mm/vmscan.c:2755
shrink_zones mm/vmscan.c:2987 [inline]
do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3049
try_to_free_pages+0x4d0/0xb90 mm/vmscan.c:3264
__perform_reclaim mm/page_alloc.c:3774 [inline]
__alloc_pages_direct_reclaim mm/page_alloc.c:3796 [inline]
__alloc_pages_slowpath+0x9ed/0x2dc0 mm/page_alloc.c:4197
__alloc_pages_nodemask+0xa80/0xde0 mm/page_alloc.c:4396
alloc_pages_current+0x173/0x350 mm/mempolicy.c:2107
alloc_pages include/linux/gfp.h:509 [inline]
__page_cache_alloc+0x38c/0x5c0 mm/filemap.c:945
__do_page_cache_readahead+0x383/0x980 mm/readahead.c:195
ra_submit mm/internal.h:66 [inline]
do_sync_mmap_readahead mm/filemap.c:2459 [inline]
filemap_fault+0xf4e/0x25f0 mm/filemap.c:2535
__do_fault+0x100/0x6b0 mm/memory.c:2991
do_read_fault mm/memory.c:3403 [inline]
do_fault mm/memory.c:3529 [inline]
handle_pte_fault mm/memory.c:3760 [inline]
__handle_mm_fault+0x3e9d/0x5bd0 mm/memory.c:3884
handle_mm_fault+0x54f/0xc70 mm/memory.c:3921
do_user_addr_fault arch/x86/mm/fault.c:1423 [inline]
__do_page_fault+0x5e8/0xe60 arch/x86/mm/fault.c:1489
do_page_fault+0xf2/0x7e0 arch/x86/mm/fault.c:1520
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1136
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x20
arch/x86/lib/copy_user_64.S:180
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 1f 00 c3 0f 1f
80 00 00 00 00 0f 1f 00 83 fa 40 0f 82 70 ff ff ff 89 d1 <f3> a4 31 c0 0f
1f 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 83
RSP: 0018:ffff8801bca7f9c0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000001000 RCX: 0000000000001000
RDX: 0000000000001000 RSI: 00000000200001c0 RDI: ffff8801a9e7d000
RBP: ffff8801bca7f9f8 R08: 0000000000000000 R09: 0000000000000040
R10: ffffed00353cfbff R11: ffff8801a9e7dfff R12: 00000000200011c0
R13: 00000000200001c0 R14: ffff8801a9e7d000 R15: 00007ffffffff000
copy_page_from_iter_iovec lib/iov_iter.c:290 [inline]
copy_page_from_iter+0x3d5/0x8e0 lib/iov_iter.c:861
pipe_write+0x238/0xec0 fs/pipe.c:429
call_write_iter include/linux/fs.h:1808 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x6b8/0x9f0 fs/read_write.c:487
vfs_write+0x1fc/0x560 fs/read_write.c:549
ksys_write+0x101/0x260 fs/read_write.c:598
__do_sys_write fs/read_write.c:610 [inline]
__se_sys_write fs/read_write.c:607 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:607
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f48a7453c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f48a74546d4
R13: 00000000004c2883 R14: 00000000004d8568 R15: 00000000ffffffff
Modules linked in:

======================================================
WARNING: possible circular locking dependency detected
4.19.0+ #84 Not tainted
------------------------------------------------------
syz-executor0/7191 is trying to acquire lock:
0000000064a5687d ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70
kernel/locking/semaphore.c:136

but task is already holding lock:
00000000ca43533e (&obj_hash[i].lock){-.-.}, at: __debug_check_no_obj_freed
lib/debugobjects.c:777 [inline]
00000000ca43533e (&obj_hash[i].lock){-.-.}, at:
debug_check_no_obj_freed+0x17a/0x58d lib/debugobjects.c:818

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&obj_hash[i].lock){-.-.}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152
__debug_object_init+0x127/0x1290 lib/debugobjects.c:384
debug_object_init+0x16/0x20 lib/debugobjects.c:432
debug_hrtimer_init kernel/time/hrtimer.c:410 [inline]
debug_init kernel/time/hrtimer.c:458 [inline]
hrtimer_init+0x97/0x490 kernel/time/hrtimer.c:1308
init_dl_task_timer+0x1b/0x50 kernel/sched/deadline.c:1057
__sched_fork+0x2ae/0x590 kernel/sched/core.c:2166
init_idle+0x75/0x800 kernel/sched/core.c:5382
sched_init+0xb33/0xc02 kernel/sched/core.c:6065
start_kernel+0x4ed/0xa5a init/main.c:607
x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:472
x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:451
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

-> #2 (&rq->lock){-.-.}:
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144
rq_lock kernel/sched/sched.h:1126 [inline]
task_fork_fair+0xb0/0x6d0 kernel/sched/fair.c:9768
sched_fork+0x443/0xba0 kernel/sched/core.c:2359
copy_process+0x2585/0x8770 kernel/fork.c:1886
_do_fork+0x1cb/0x11d0 kernel/fork.c:2213
kernel_thread+0x34/0x40 kernel/fork.c:2272
rest_init+0x28/0x372 init/main.c:408
arch_call_rest_init+0xe/0x1b
start_kernel+0xa1f/0xa5a init/main.c:744
x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:472
x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:451
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

-> #1 (&p->pi_lock){-.-.}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152
try_to_wake_up+0xd2/0x12e0 kernel/sched/core.c:1965
wake_up_process+0x10/0x20 kernel/sched/core.c:2129
__up.isra.1+0x1c0/0x2a0 kernel/locking/semaphore.c:262
up+0x13c/0x1c0 kernel/locking/semaphore.c:187
__up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:237
console_unlock+0x811/0x1190 kernel/printk/printk.c:2433
vprintk_emit+0x391/0x990 kernel/printk/printk.c:1923
vprintk_default+0x28/0x30 kernel/printk/printk.c:1965
vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398
printk+0xa7/0xcf kernel/printk/printk.c:1998
check_stack_usage kernel/exit.c:755 [inline]
do_exit.cold.18+0x57/0x16f kernel/exit.c:916
do_group_exit+0x177/0x440 kernel/exit.c:970
__do_sys_exit_group kernel/exit.c:981 [inline]
__se_sys_exit_group kernel/exit.c:979 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:979
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #0 ((console_sem).lock){-.-.}:
lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152
down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
__down_trylock_console_sem+0xae/0x1f0 kernel/printk/printk.c:220
console_trylock+0x15/0xa0 kernel/printk/printk.c:2248
console_trylock_spinning kernel/printk/printk.c:1654 [inline]
vprintk_emit+0x372/0x990 kernel/printk/printk.c:1922
vprintk_default+0x28/0x30 kernel/printk/printk.c:1965
vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398
printk+0xa7/0xcf kernel/printk/printk.c:1998
kasan_die_handler.cold.20+0x11/0x2f arch/x86/mm/kasan_init_64.c:251
notifier_call_chain+0x17e/0x380 kernel/notifier.c:93
__atomic_notifier_call_chain kernel/notifier.c:183 [inline]
atomic_notifier_call_chain+0x96/0x190 kernel/notifier.c:193
notify_die+0x1bd/0x2d0 kernel/notifier.c:549
do_general_protection+0x16d/0x2f0 arch/x86/kernel/traps.c:557
general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1135
__debug_check_no_obj_freed lib/debugobjects.c:778 [inline]
debug_check_no_obj_freed+0x1bb/0x58d lib/debugobjects.c:818
free_pages_prepare mm/page_alloc.c:1035 [inline]
free_pcp_prepare mm/page_alloc.c:1049 [inline]
free_unref_page_prepare mm/page_alloc.c:2744 [inline]
free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2813
shrink_page_list+0x6dc3/0xccd0 mm/vmscan.c:1501
shrink_inactive_list+0x77b/0x1c60 mm/vmscan.c:1963
shrink_list mm/vmscan.c:2275 [inline]
shrink_node_memcg+0x78b/0x18f0 mm/vmscan.c:2540
shrink_node+0x3bc/0x16b0 mm/vmscan.c:2755
shrink_zones mm/vmscan.c:2987 [inline]
do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3049
try_to_free_pages+0x4d0/0xb90 mm/vmscan.c:3264
__perform_reclaim mm/page_alloc.c:3774 [inline]
__alloc_pages_direct_reclaim mm/page_alloc.c:3796 [inline]
__alloc_pages_slowpath+0x9ed/0x2dc0 mm/page_alloc.c:4197
__alloc_pages_nodemask+0xa80/0xde0 mm/page_alloc.c:4396
alloc_pages_current+0x173/0x350 mm/mempolicy.c:2107
alloc_pages include/linux/gfp.h:509 [inline]
__page_cache_alloc+0x38c/0x5c0 mm/filemap.c:945
__do_page_cache_readahead+0x383/0x980 mm/readahead.c:195
ra_submit mm/internal.h:66 [inline]
do_sync_mmap_readahead mm/filemap.c:2459 [inline]
filemap_fault+0xf4e/0x25f0 mm/filemap.c:2535
__do_fault+0x100/0x6b0 mm/memory.c:2991
do_read_fault mm/memory.c:3403 [inline]
do_fault mm/memory.c:3529 [inline]
handle_pte_fault mm/memory.c:3760 [inline]
__handle_mm_fault+0x3e9d/0x5bd0 mm/memory.c:3884
handle_mm_fault+0x54f/0xc70 mm/memory.c:3921
do_user_addr_fault arch/x86/mm/fault.c:1423 [inline]
__do_page_fault+0x5e8/0xe60 arch/x86/mm/fault.c:1489
do_page_fault+0xf2/0x7e0 arch/x86/mm/fault.c:1520
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1136
copy_user_enhanced_fast_string+0xe/0x20
arch/x86/lib/copy_user_64.S:180
copy_page_from_iter_iovec lib/iov_iter.c:290 [inline]
copy_page_from_iter+0x3d5/0x8e0 lib/iov_iter.c:861
pipe_write+0x238/0xec0 fs/pipe.c:429
call_write_iter include/linux/fs.h:1808 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x6b8/0x9f0 fs/read_write.c:487
vfs_write+0x1fc/0x560 fs/read_write.c:549
ksys_write+0x101/0x260 fs/read_write.c:598
__do_sys_write fs/read_write.c:610 [inline]
__se_sys_write fs/read_write.c:607 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:607
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
(console_sem).lock --> &rq->lock --> &obj_hash[i].lock

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&obj_hash[i].lock);
lock(&rq->lock);
lock(&obj_hash[i].lock);
lock((console_sem).lock);

*** DEADLOCK ***

5 locks held by syz-executor0/7191:
#0: 00000000845196d1 (&pipe->mutex/1){+.+.}, at: __pipe_lock fs/pipe.c:83
[inline]
#0: 00000000845196d1 (&pipe->mutex/1){+.+.}, at: pipe_write+0xc0/0xec0
fs/pipe.c:366
#1: 000000008df14d85 (&mm->mmap_sem){++++}, at: do_user_addr_fault
arch/x86/mm/fault.c:1351 [inline]
#1: 000000008df14d85 (&mm->mmap_sem){++++}, at:
__do_page_fault+0x3da/0xe60 arch/x86/mm/fault.c:1489
#2: 000000004ae662d4 (fs_reclaim){+.+.}, at:
fs_reclaim_acquire.part.100+0x0/0x30 mm/internal.h:79
#3: 00000000ca43533e (&obj_hash[i].lock){-.-.}, at:
__debug_check_no_obj_freed lib/debugobjects.c:777 [inline]
#3: 00000000ca43533e (&obj_hash[i].lock){-.-.}, at:
debug_check_no_obj_freed+0x17a/0x58d lib/debugobjects.c:818
#4: 0000000021ea63ad (rcu_read_lock){....}, at:
atomic_notifier_call_chain+0x0/0x190 kernel/notifier.c:329

stack backtrace:
CPU: 1 PID: 7191 Comm: syz-executor0 Not tainted 4.19.0+ #84
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x244/0x39d lib/dump_stack.c:113
print_circular_bug.isra.35.cold.54+0x1bd/0x27d
kernel/locking/lockdep.c:1221
check_prev_add kernel/locking/lockdep.c:1863 [inline]
check_prevs_add kernel/locking/lockdep.c:1976 [inline]
validate_chain kernel/locking/lockdep.c:2347 [inline]
__lock_acquire+0x3399/0x4c20 kernel/locking/lockdep.c:3341
lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152
down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
__down_trylock_console_sem+0xae/0x1f0 kernel/printk/printk.c:220
console_trylock+0x15/0xa0 kernel/printk/printk.c:2248
console_trylock_spinning kernel/printk/printk.c:1654 [inline]
vprintk_emit+0x372/0x990 kernel/printk/printk.c:1922
vprintk_default+0x28/0x30 kernel/printk/printk.c:1965
vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398
printk+0xa7/0xcf kernel/printk/printk.c:1998
kasan_die_handler.cold.20+0x11/0x2f arch/x86/mm/kasan_init_64.c:251
notifier_call_chain+0x17e/0x380 kernel/notifier.c:93
__atomic_notifier_call_chain kernel/notifier.c:183 [inline]
atomic_notifier_call_chain+0x96/0x190 kernel/notifier.c:193
notify_die+0x1bd/0x2d0 kernel/notifier.c:549
do_general_protection+0x16d/0x2f0 arch/x86/kernel/traps.c:557
general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1135
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:778 [inline]
RIP: 0010:debug_check_no_obj_freed+0x1bb/0x58d lib/debugobjects.c:818
Code: 48 8b b5 48 ff ff ff 48 c7 c0 60 fe f9 8a 4c 8b 2c 30 4d 85 ed 0f 84
87 02 00 00 31 f6 4d 89 e7 41 89 f4 4c 89 e8 48 c1 e8 03 <42> 80 3c 30 00
0f 85 91 02 00 00 49 8d 7d 18 41 83 c4 01 49 8b 5d
RSP: 0018:ffff8801bca7b148 EFLAGS: 00010006
RAX: 0407040646640706 RBX: 2038203233203833 RCX: 0000000000000001
RDX: 3320382030363120 RSI: 0000000000000000 RDI: ffffffff890113b0
RBP: ffff8801bca7b238 R08: ffffed003794f616 R09: ffffed003794f615
R10: ffffed003794f615 R11: 0000000000000003 R12: 0000000000000004
R13: 2038203233203833 R14: dffffc0000000000 R15: ffffffff8b030c68
free_pages_prepare mm/page_alloc.c:1035 [inline]
free_pcp_prepare mm/page_alloc.c:1049 [inline]
free_unref_page_prepare mm/page_alloc.c:2744 [inline]
free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2813
shrink_page_list+0x6dc3/0xccd0 mm/vmscan.c:1501

Lost 299 message(s)!
---[ end trace 1b68d1f4b97ce759 ]---
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:778 [inline]
RIP: 0010:debug_check_no_obj_freed+0x1bb/0x58d lib/debugobjects.c:818
Code: 48 8b b5 48 ff ff ff 48 c7 c0 60 fe f9 8a 4c 8b 2c 30 4d 85 ed 0f 84
87 02 00 00 31 f6 4d 89 e7 41 89 f4 4c 89 e8 48 c1 e8 03 <42> 80 3c 30 00
0f 85 91 02 00 00 49 8d 7d 18 41 83 c4 01 49 8b 5d
RSP: 0018:ffff8801bca7b148 EFLAGS: 00010006
RAX: 0407040646640706 RBX: 2038203233203833 RCX: 0000000000000001
RDX: 3320382030363120 RSI: 0000000000000000 RDI: ffffffff890113b0
RBP: ffff8801bca7b238 R08: ffffed003794f616 R09: ffffed003794f615
R10: ffffed003794f615 R11: 0000000000000003 R12: 0000000000000004
R13: 2038203233203833 R14: dffffc0000000000 R15: ffffffff8b030c68
FS: 00007f48a7454700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 0000000160d3f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.