INFO: task syz.4.720:7439 blocked for more than 143 seconds.
      Not tainted 5.15.175-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.720       state:D stack:26616 pid: 7439 ppid:  4166 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 inode_lock include/linux/fs.h:789 [inline]
 open_last_lookups fs/namei.c:3529 [inline]
 path_openat+0x824/0x2f20 fs/namei.c:3739
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb1cbb17d29
RSP: 002b:00007fb1c9967038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb1cbd08080 RCX: 00007fb1cbb17d29
RDX: 0000000000141042 RSI: 0000000020000600 RDI: ffffffffffffff9c
RBP: 00007fb1cbb93aa8 R08: 0000000000000000 R09: 0000000000000000
R10: dda01e4938171605 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fb1cbd08080 R15: 00007ffcd088db48
 </TASK>
INFO: task syz.4.720:7440 blocked for more than 144 seconds.
      Not tainted 5.15.175-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.720       state:D stack:27448 pid: 7440 ppid:  4166 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 inode_lock_shared include/linux/fs.h:799 [inline]
 lookup_slow+0x45/0x70 fs/namei.c:1679
 walk_component+0x48c/0x610 fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2455
 filename_lookup+0x230/0x5c0 fs/namei.c:2484
 user_path_at_empty+0x40/0x180 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 path_setxattr+0xae/0x2a0 fs/xattr.c:625
 __do_sys_lsetxattr fs/xattr.c:653 [inline]
 __se_sys_lsetxattr fs/xattr.c:649 [inline]
 __x64_sys_lsetxattr+0xb4/0xd0 fs/xattr.c:649
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb1cbb17d29
RSP: 002b:00007fb1c9946038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007fb1cbd08160 RCX: 00007fb1cbb17d29
RDX: 0000000020000280 RSI: 0000000020000140 RDI: 0000000020000000
RBP: 00007fb1cbb93aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fb1cbd08160 R15: 00007ffcd088db48
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by udevd/3546:
2 locks held by getty/3925:
 #0: ffff88814c753098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by udevd/4187:
2 locks held by syz-executor/6510:
 #0: ffff888020c0bd18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
 #1: ffff8881475ac468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365
1 lock held by syz.4.720/7438:
1 lock held by syz.4.720/7439:
 #0: ffff8880568ac188 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #0: ffff8880568ac188 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: open_last_lookups fs/namei.c:3529 [inline]
 #0: ffff8880568ac188 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: path_openat+0x824/0x2f20 fs/namei.c:3739
1 lock held by syz.4.720/7440:
 #0: ffff8880568ac188 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:799 [inline]
 #0: ffff8880568ac188 (&type->i_mutex_dir_key#26){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1679
2 locks held by syz.0.1077/9249:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4577 Comm: kworker/u4:11 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: loop0 loop_workfn
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x30/0x80 kernel/kcov.c:300
Code: 8b 0d f4 e6 81 7e 65 8b 05 f5 e6 81 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 57 83 b9 34 16 00 00 00 74 4e 8b 81 10 16 00 00 <83> f8 03 75 43 48 8b 91 18 16 00 00 44 8b 89 14 16 00 00 49 c1 e1
RSP: 0018:ffffc9000133eff0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffea0000c62080 RCX: ffff888023fa5940
RDX: 0000000000000000 RSI: 00fff0000008002c RDI: ffffffffffffffff
RBP: ffffea0000c62088 R08: ffffffff81ad7c6f R09: fffff9400018c411
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: dffffc0000000000 R14: 00fff0000008002c R15: ffffea0000c62080
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9f030f1178 CR3: 000000002b4d7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 PagePoisoned include/linux/page-flags.h:218 [inline]
 PageUnevictable include/linux/page-flags.h:424 [inline]
 page_lru include/linux/mm_inline.h:70 [inline]
 add_page_to_lru_list include/linux/mm_inline.h:85 [inline]
 __activate_page+0xb8f/0x17b0 mm/swap.c:305
 pagevec_lru_move_fn+0x38b/0x670 mm/swap.c:197
 activate_page mm/swap.c:338 [inline]
 mark_page_accessed+0xcde/0x1330 mm/swap.c:422
 shmem_getpage_gfp+0x4bc/0x3190 mm/shmem.c:1866
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xce/0x1a0 mm/shmem.c:2474
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 do_iter_readv_writev+0x594/0x7a0
 do_iter_write+0x1e6/0x760 fs/read_write.c:855
 lo_write_bvec+0x297/0x740 drivers/block/loop.c:316
 lo_write_simple drivers/block/loop.c:338 [inline]
 do_req_filebacked drivers/block/loop.c:656 [inline]
 loop_handle_cmd drivers/block/loop.c:2234 [inline]
 loop_process_work+0x2309/0x2af0 drivers/block/loop.c:2274
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>