[syzbot] BUG: sleeping function called from invalid context in check_noncircular

From: syzbot
Date: Tue Aug 23 2022 - 13:19:18 EST


Hello,

syzbot found the following issue on:

HEAD commit: 8755ae45a9e8 Add linux-next specific files for 20220819
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16960ab5080000
kernel config: https://syzkaller.appspot.com/x/.config?x=ead6107a3bbe3c62
dashboard link: https://syzkaller.appspot.com/bug?extid=d709b1e8ea3167a1f513
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d709b1e8ea3167a1f513@xxxxxxxxxxxxxxxxxxxxxxxxx

CPU: 1 PID: 5779 Comm: syz-executor.5 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1521
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 5779, name: syz-executor.5
preempt_count: 0, expected: 0
RCU nest depth: 0, expected: 0
5 locks held by syz-executor.5/5779:
#0: ffff8880173565e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe3/0x100 fs/file.c:1036
#1: ffff888021202460 (sb_writers#10){.+.+}-{0:0}, at: ksys_write+0x127/0x250 fs/read_write.c:631
#2: ffff8880245aec88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x28c/0x610 fs/kernfs/file.c:345
#3: ffff88807d20a748 (kn->active#223){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b0/0x610 fs/kernfs/file.c:346
#4: ffffffff8c0780a8 (oom_lock){+.+.}-{3:3}, at: mem_cgroup_out_of_memory+0x8d/0x270 mm/memcontrol.c:1642
irq event stamp: 4106
hardirqs last enabled at (4105): [<ffffffff816756cd>] call_rcu+0x2dd/0x790 kernel/rcu/tree.c:2828
hardirqs last disabled at (4106): [<ffffffff894c1738>] dump_stack_lvl+0x2e/0x134 lib/dump_stack.c:139
softirqs last enabled at (4084): [<ffffffff81491a33>] invoke_softirq kernel/softirq.c:445 [inline]
softirqs last enabled at (4084): [<ffffffff81491a33>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
softirqs last disabled at (4063): [<ffffffff81491a33>] invoke_softirq kernel/softirq.c:445 [inline]
softirqs last disabled at (4063): [<ffffffff81491a33>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
CPU: 1 PID: 5779 Comm: syz-executor.5 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0

======================================================
WARNING: possible circular locking dependency detected
6.0.0-rc1-next-20220819-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.5/5779 is trying to acquire lock:
ffff88807b920828 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
ffff88807b920828 (&mm->mmap_lock#2){++++}-{3:3}, at: __access_remote_vm+0xac/0x6f0 mm/memory.c:5461

but task is already holding lock:
ffffffff8c0780a8 (oom_lock){+.+.}-{3:3}, at: mem_cgroup_out_of_memory+0x8d/0x270 mm/memcontrol.c:1642

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (oom_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747
mem_cgroup_out_of_memory+0x8d/0x270 mm/memcontrol.c:1642
mem_cgroup_oom mm/memcontrol.c:1882 [inline]
try_charge_memcg+0xf13/0x1300 mm/memcontrol.c:2675
try_charge mm/memcontrol.c:2769 [inline]
charge_memcg+0x31/0x320 mm/memcontrol.c:6816
__mem_cgroup_charge+0x27/0x90 mm/memcontrol.c:6837
mem_cgroup_charge include/linux/memcontrol.h:696 [inline]
wp_page_copy+0x27c/0x1b60 mm/memory.c:3122
do_wp_page+0x1d1/0x1910 mm/memory.c:3393
handle_pte_fault mm/memory.c:4926 [inline]
__handle_mm_fault+0x184b/0x3a90 mm/memory.c:5050
handle_mm_fault+0x1c8/0x780 mm/memory.c:5171
do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1399
handle_page_fault arch/x86/mm/fault.c:1490 [inline]
exc_page_fault+0x94/0x170 arch/x86/mm/fault.c:1546
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570

-> #0 (&mm->mmap_lock#2){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3095 [inline]
check_prevs_add kernel/locking/lockdep.c:3214 [inline]
validate_chain kernel/locking/lockdep.c:3829 [inline]
__lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053
lock_acquire kernel/locking/lockdep.c:5666 [inline]
lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
down_read_killable+0x9b/0x490 kernel/locking/rwsem.c:1522
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9896
down_read_killable+0x75/0x490 kernel/locking/rwsem.c:1521
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
dump_header+0x10b/0x7f9 mm/oom_kill.c:460
oom_kill_process.cold+0x10/0x15 mm/oom_kill.c:1036
out_of_memory+0x358/0x14a0 mm/oom_kill.c:1174
mem_cgroup_out_of_memory+0x206/0x270 mm/memcontrol.c:1652
memory_max_write+0x2f5/0x3c0 mm/memcontrol.c:6392
cgroup_file_write+0x1de/0x770 kernel/cgroup/cgroup.c:3930
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
call_write_iter include/linux/fs.h:2188 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x127/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(oom_lock);
lock(&mm->mmap_lock#2);
lock(oom_lock);
lock(&mm->mmap_lock#2);

*** DEADLOCK ***

5 locks held by syz-executor.5/5779:
#0: ffff8880173565e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe3/0x100 fs/file.c:1036
#1: ffff888021202460 (sb_writers#10){.+.+}-{0:0}, at: ksys_write+0x127/0x250 fs/read_write.c:631
#2: ffff8880245aec88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x28c/0x610 fs/kernfs/file.c:345
#3: ffff88807d20a748 (kn->active#223){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b0/0x610 fs/kernfs/file.c:346
#4: ffffffff8c0780a8 (oom_lock){+.+.}-{3:3}, at: mem_cgroup_out_of_memory+0x8d/0x270 mm/memcontrol.c:1642

stack backtrace:
CPU: 1 PID: 5779 Comm: syz-executor.5 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0
syz-executor.5[5779] cmdline: /root/syz-executor.5 exec
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:122 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140
check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3095 [inline]
check_prevs_add kernel/locking/lockdep.c:3214 [inline]
validate_chain kernel/locking/lockdep.c:3829 [inline]
__lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053
lock_acquire kernel/locking/lockdep.c:5666 [inline]
lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
down_read_killable+0x9b/0x490 kernel/locking/rwsem.c:1522
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9896
down_read_killable+0x75/0x490 kernel/locking/rwsem.c:1521
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
dump_header+0x10b/0x7f9 mm/oom_kill.c:460
oom_kill_process.cold+0x10/0x15 mm/oom_kill.c:1036
out_of_memory+0x358/0x14a0 mm/oom_kill.c:1174
mem_cgroup_out_of_memory+0x206/0x270 mm/memcontrol.c:1652
memory_max_write+0x2f5/0x3c0 mm/memcontrol.c:6392
cgroup_file_write+0x1de/0x770 kernel/cgroup/cgroup.c:3930
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
call_write_iter include/linux/fs.h:2188 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x127/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f47db689279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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:00007f47dc719168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f47db79bf80 RCX: 00007f47db689279
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 00007f47db6e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffce4a733f R14: 00007f47dc719300 R15: 0000000000022000
</TASK>
BUG: sleeping function called from invalid context at mm/gup.c:1215
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 5779, name: syz-executor.5
preempt_count: 0, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
irq event stamp: 4106
hardirqs last enabled at (4105): [<ffffffff816756cd>] call_rcu+0x2dd/0x790 kernel/rcu/tree.c:2828
hardirqs last disabled at (4106): [<ffffffff894c1738>] dump_stack_lvl+0x2e/0x134 lib/dump_stack.c:139
softirqs last enabled at (4084): [<ffffffff81491a33>] invoke_softirq kernel/softirq.c:445 [inline]
softirqs last enabled at (4084): [<ffffffff81491a33>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
softirqs last disabled at (4063): [<ffffffff81491a33>] invoke_softirq kernel/softirq.c:445 [inline]
softirqs last disabled at (4063): [<ffffffff81491a33>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
CPU: 1 PID: 5779 Comm: syz-executor.5 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0
syz-executor.5[5779] cmdline: /root/syz-executor.5 exec
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:122 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9896
__get_user_pages+0x451/0xfd0 mm/gup.c:1215
__get_user_pages_locked mm/gup.c:1423 [inline]
__get_user_pages_remote+0x18f/0x830 mm/gup.c:2133
get_user_pages_remote+0x84/0xc0 mm/gup.c:2206
__access_remote_vm+0x275/0x6f0 mm/memory.c:5470
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9896
down_read_killable+0x75/0x490 kernel/locking/rwsem.c:1521
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
dump_header+0x10b/0x7f9 mm/oom_kill.c:460
oom_kill_process.cold+0x10/0x15 mm/oom_kill.c:1036
out_of_memory+0x358/0x14a0 mm/oom_kill.c:1174
mem_cgroup_out_of_memory+0x206/0x270 mm/memcontrol.c:1652
memory_max_write+0x2f5/0x3c0 mm/memcontrol.c:6392
cgroup_file_write+0x1de/0x770 kernel/cgroup/cgroup.c:3930
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
call_write_iter include/linux/fs.h:2188 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x127/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f47db689279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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:00007f47dc719168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f47db79bf80 RCX: 00007f47db689279
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 00007f47db6e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffce4a733f R14: 00007f47dc719300 R15: 0000000000022000
</TASK>
syz-executor.5[5779] cmdline: /root/syz-executor.5 exec
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:122 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140
__might_resched.cold+0x222/0x26b kernel/sched/core.c:9896
down_read_killable+0x75/0x490 kernel/locking/rwsem.c:1521
mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline]
__access_remote_vm+0xac/0x6f0 mm/memory.c:5461
get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299
get_mm_cmdline fs/proc/base.c:367 [inline]
get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367
dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61
dump_stack_print_cmdline lib/dump_stack.c:89 [inline]
dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97
__dump_stack lib/dump_stack.c:121 [inline]
dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140
dump_header+0x10b/0x7f9 mm/oom_kill.c:460
oom_kill_process.cold+0x10/0x15 mm/oom_kill.c:1036
out_of_memory+0x358/0x14a0 mm/oom_kill.c:1174
mem_cgroup_out_of_memory+0x206/0x270 mm/memcontrol.c:1652
memory_max_write+0x2f5/0x3c0 mm/memcontrol.c:6392
cgroup_file_write+0x1de/0x770 kernel/cgroup/cgroup.c:3930
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
call_write_iter include/linux/fs.h:2188 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x127/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f47db689279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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:00007f47dc719168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f47db79bf80 RCX: 00007f47db689279
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 00007f47db6e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffce4a733f R14: 00007f47dc719300 R15: 0000000000022000
</TASK>
syz-executor.5[5779] cmdline: /root/syz-executor.5 exec
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:122 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140
dump_header+0x10b/0x7f9 mm/oom_kill.c:460
oom_kill_process.cold+0x10/0x15 mm/oom_kill.c:1036
out_of_memory+0x358/0x14a0 mm/oom_kill.c:1174
mem_cgroup_out_of_memory+0x206/0x270 mm/memcontrol.c:1652
memory_max_write+0x2f5/0x3c0 mm/memcontrol.c:6392
cgroup_file_write+0x1de/0x770 kernel/cgroup/cgroup.c:3930
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:354
call_write_iter include/linux/fs.h:2188 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x127/0x250 fs/read_write.c:631
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f47db689279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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:00007f47dc719168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f47db79bf80 RCX: 00007f47db689279
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 00007f47db6e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffce4a733f R14: 00007f47dc719300 R15: 0000000000022000
</TASK>
memory: usage 432kB, limit 0kB, failcnt 27
swap: usage 0kB, limit 9007199254740988kB, failcnt 0
Memory cgroup stats for /syz1:
anon 122880
file 57344
kernel 262144
kernel_stack 65536
pagetables 81920
percpu 0
sock 0
vmalloc 0
shmem 36864
zswap 0
zswapped 0
file_mapped 36864
file_dirty 4096
file_writeback 0
swapcached 0
anon_thp 0
file_thp 0
shmem_thp 0
inactive_anon 139264
active_anon 20480
inactive_file 12288
active_file 8192
unevictable 0
slab_reclaimable 12008
slab_unreclaimable 76488
slab 88496
oom-kill:constraint=CONSTRAINT_MEMCG,nodemask=(null),cpuset=syz5,mems_allowed=0-1,oom_memcg=/syz1,task_memcg=/syz1,task=syz-executor.1,pid=3746,uid=0
Memory cgroup out of memory: Killed process 3746 (syz-executor.1) total-vm:50536kB, anon-rss:392kB, file-rss:9072kB, shmem-rss:4kB, UID:0 pgtables:72kB oom_score_adj:0


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