INFO: task kworker/u8:6:146 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:6 state:D stack:23712 pid:146 tgid:146 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 io_schedule+0x7f/0xd0 kernel/sched/core.c:7831 folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1170 [inline] writeback_get_folio mm/page-writeback.c:2418 [inline] writeback_iter+0x8d8/0x12c0 mm/page-writeback.c:2512 blkdev_writepages+0xd5/0x1b0 block/fops.c:486 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 __writeback_single_inode+0x133/0x11a0 fs/fs-writeback.c:1750 writeback_sb_inodes+0x944/0x19a0 fs/fs-writeback.c:2041 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2118 wb_writeback+0x46a/0xb70 fs/fs-writeback.c:2229 wb_check_start_all fs/fs-writeback.c:2355 [inline] wb_do_writeback fs/fs-writeback.c:2381 [inline] wb_workfn+0x95b/0xf50 fs/fs-writeback.c:2414 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task udevd:6280 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24544 pid:6280 tgid:6280 ppid:5192 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 bdev_release+0x1a9/0x650 block/bdev.c:1144 blkdev_release+0x15/0x20 block/fops.c:706 __fput+0x44f/0xa70 fs/file_table.c:469 fput_close_sync+0x11f/0x240 fs/file_table.c:574 __do_sys_close fs/open.c:1509 [inline] __se_sys_close fs/open.c:1494 [inline] __x64_sys_close+0x7e/0x110 fs/open.c:1494 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f82a80a7407 RSP: 002b:00007ffce344f330 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 00007f82a87a8880 RCX: 00007f82a80a7407 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000009 RBP: 00007f82a87a86e8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000003 R14: 00007ffce344f3e0 R15: 0000000000000009 INFO: task syz.4.68:6711 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.68 state:D stack:25408 pid:6711 tgid:6709 ppid:6353 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 io_schedule+0x7f/0xd0 kernel/sched/core.c:7831 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250 __wait_on_bit_lock+0xec/0x4e0 kernel/sched/wait_bit.c:93 out_of_line_wait_on_bit_lock+0x13b/0x190 kernel/sched/wait_bit.c:120 wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline] __lock_buffer fs/buffer.c:72 [inline] lock_buffer include/linux/buffer_head.h:432 [inline] __block_write_full_folio+0x54f/0xe10 fs/buffer.c:1908 blkdev_writepages+0xef/0x1b0 block/fops.c:487 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 filemap_writeback mm/filemap.c:387 [inline] filemap_fdatawrite_range mm/filemap.c:412 [inline] filemap_fdatawrite+0x1e9/0x2f0 mm/filemap.c:418 sync_bdevs+0x30a/0x470 block/bdev.c:1316 ksys_sync fs/sync.c:105 [inline] __ia32_sys_sync+0xc5/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f77e399a339 RSP: 002b:00007f77e2ffe028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f77e3bd5fa0 RCX: 00007f77e399a339 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f77e3bd5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f77e3bd6038 R14: 00007f77e3bd5fa0 R15: 00007fff24290548 INFO: task syz.0.71:6715 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.71 state:D stack:25632 pid:6715 tgid:6710 ppid:6339 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 io_schedule+0x7f/0xd0 kernel/sched/core.c:7831 folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1170 [inline] __find_get_block_slow fs/buffer.c:206 [inline] find_get_block_common+0x34f/0xe10 fs/buffer.c:1406 bdev_getblk+0x53/0x6e0 include/linux/gfp.h:-1 __bread_gfp+0x89/0x3b0 fs/buffer.c:1513 sb_bread include/linux/buffer_head.h:346 [inline] hfs_mdb_commit+0xc04/0x12c0 fs/hfs/mdb.c:324 hfs_sync_fs+0x15/0x20 fs/hfs/super.c:37 __iterate_supers+0x13d/0x290 fs/super.c:927 ksys_sync fs/sync.c:103 [inline] __ia32_sys_sync+0xaf/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f814079a339 RSP: 002b:00007f81415e8028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f81409d5fa0 RCX: 00007f814079a339 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f81409d5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f81409d6038 R14: 00007f81409d5fa0 R15: 00007fffd5aa7948 INFO: task syz.2.70:6714 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.70 state:D stack:27328 pid:6714 tgid:6712 ppid:6341 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 sync_bdevs+0x27e/0x470 block/bdev.c:1304 ksys_sync fs/sync.c:105 [inline] __ia32_sys_sync+0xc5/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1fcb39a339 RSP: 002b:00007f1fcc1f9028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f1fcb5d5fa0 RCX: 00007f1fcb39a339 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f1fcb5d5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1fcb5d6038 R14: 00007f1fcb5d5fa0 R15: 00007fff422239a8 INFO: task syz.3.72:6716 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.72 state:D stack:25632 pid:6716 tgid:6713 ppid:6352 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5310 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 wb_wait_for_completion+0x372/0x690 fs/fs-writeback.c:226 sync_inodes_sb+0x1de/0xbd0 fs/fs-writeback.c:2924 __iterate_supers+0x13d/0x290 fs/super.c:927 ksys_sync fs/sync.c:102 [inline] __ia32_sys_sync+0xa0/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdcc4d9a339 RSP: 002b:00007fdcc5be2028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fdcc4fd5fa0 RCX: 00007fdcc4d9a339 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fdcc4fd5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdcc4fd6038 R14: 00007fdcc4fd5fa0 R15: 00007ffe9dbdf368 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:5/105: 3 locks held by kworker/u8:6/146: #0: ffff8880206d9148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc90002ea7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 #2: ffff88801c6f00e0 (&type->s_umount_key#42){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 4 locks held by kworker/u8:9/1329: #0: ffff8880b873ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8726118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30 kernel/time/timer.c:1117 #3: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #3: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #3: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: ieee80211_sta_active_ibss+0xc3/0x330 net/mac80211/ibss.c:635 2 locks held by getty/5579: #0: ffff88803696b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by udevd/6280: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144 2 locks held by kworker/0:7/6557: #0: ffff88801b06ad48 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc90003387c40 ((work_completion)(&(&sbi->mdb_work)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 1 lock held by syz.4.68/6711: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304 1 lock held by syz.0.71/6715: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.2.70/6714: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1304 2 locks held by syz.3.72/6716: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.1.73/6719: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.6.75/7124: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.7.76/7126: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.5.74/7128: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.9.78/7130: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.8.77/7132: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 1 lock held by syz-executor/7134: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961 2 locks held by syz.4.83/7241: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.2.81/7243: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.3.82/7245: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.1.80/7247: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.6.84/7277: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.5.85/7344: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.8.87/7378: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.9.88/7380: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.7.86/7382: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 1 lock held by syz-executor/7384: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961 2 locks held by syz.4.90/7440: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.1.91/7483: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.2.92/7489: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.3.93/7491: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.6.94/7518: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.5.95/7546: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.8.97/7632: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 1 lock held by syz-executor/7633: #0: ffff888026a09358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961 2 locks held by syz.7.96/7639: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.9.98/7644: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.4.100/7681: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.1.101/7753: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.2.102/7757: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.3.103/7770: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.6.104/7780: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 2 locks held by syz.5.105/7799: #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805f7a60e0 (&type->s_umount_key#71){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff8880269ea820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2922 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1349 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:memset_orig+0x46/0xb0 arch/x86/lib/memset_64.S:74 Code: 75 74 48 89 d1 48 c1 e9 06 74 39 66 0f 1f 84 00 00 00 00 00 48 ff c9 48 89 07 48 89 47 08 48 89 47 10 48 89 47 18 48 89 47 20 <48> 89 47 28 48 89 47 30 48 89 47 38 48 8d 7f 40 75 d8 0f 1f 84 00 RSP: 0018:ffffc90005c1f728 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000082820 RCX: 0000000000000005 RDX: 0000000000000200 RSI: 0000000000000000 RDI: ffffc90005c1f7b0 RBP: ffffc90005c1f958 R08: dffffc0000000000 R09: 0000000000000000 R10: ffffc90005c1f730 R11: fffffbfff20229b7 R12: ffff88801b042140 R13: 00000000ffffffff R14: ffff888076e1f000 R15: ffffc90005c1f730 FS: 0000000000000000(0000) GS:ffff888125569000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557ef4e4e8 CR3: 000000007f306000 CR4: 00000000003526f0 Call Trace: kasan_save_stack mm/kasan/common.c:54 [inline] kasan_save_track+0x2f/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5177 [inline] __kmalloc_node_track_caller_noprof+0x4db/0x7b0 mm/slub.c:5285 kmalloc_reserve net/core/skbuff.c:635 [inline] __alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:922 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245