INFO: task kworker/u8:6:190 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:21504 pid:190 tgid:190 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_w[ 440.302190][ T38] Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2dc/0x7b0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552
jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75d/0x11a0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x995/0x19d0 fs/fs-writeback.c:2054
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2130
wb_writeback+0x46a/0xb70 fs/fs-writeback.c:2241
wb_check_start_all fs/fs-writeback.c:2367 [inline]
wb_do_writeback fs/fs-writeback.c:2393 [inline]
wb_workfn+0x961/0xf60 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3288 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3371
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452
kthread+0x388/0x470 kernel/kthread.c:436
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 syz.5.334:8498 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.334 state:D stack:24768 pid:8498 tgid:8497 ppid:6458 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
io_schedule+0x80/0xe0 kernel/sched/core.c:7835
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1159 [inline]
release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753
dtSplitPage+0x791/0x37c0 fs/jfs/jfs_dtree.c:1471
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x10a4/0x5f10 fs/jfs/jfs_dtree.c:871
jfs_create+0x75b/0xb10 fs/jfs/namei.c:138
lookup_open fs/namei.c:4489 [inline]
open_last_lookups fs/namei.c:4589 [inline]
path_openat+0x13b4/0x38a0 fs/namei.c:4833
do_file_open+0x23e/0x4a0 fs/namei.c:4865
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
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: 0033:0x7ff33347c819
RSP: 002b:00007ff3316ce028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff3336f5fa0 RCX: 00007ff33347c819
RDX: 000000000000275a RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007ff333512c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff3336f6038 R14: 00007ff3336f5fa0 R15: 00007ffea79c6fc8
INFO: task syz.7.337:8501 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.337 state:D stack:25440 pid:8501 tgid:8500 ppid:7540 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
sync_inodes_sb+0x225/0xc30 fs/fs-writeback.c:2942
__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: 0033:0x7fd94ec0c819
RSP: 002b:00007fd94ce5e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fd94ee85fa0 RCX: 00007fd94ec0c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd94ee85fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd94ee86038 R14: 00007fd94ee85fa0 R15: 00007ffef1d1d658
Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/38:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/57:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc9000123fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc9000123fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff8880532308b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline]
#2: ffff8880532308b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x4a0 net/wireless/core.c:426
#3: ffff8880b8829400 ((lock)#3){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff8880b8829400 ((lock)#3){+.+.}-{3:3}, at: kcov_remote_start+0xe0/0x710 kernel/kcov.c:877
3 locks held by kworker/u8:5/117:
4 locks held by kworker/u8:6/190:
#0: ffff88801aee4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff88801aee4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc90003b97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc90003b97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff8880640820d0 (&type->s_umount_key#72){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff88806070c628 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by kworker/u8:8/1115:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc9000532fc40 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc9000532fc40 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
3 locks held by kworker/u8:10/1166:
#0: ffff888031f58138 ((wq_completion)loop3){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff888031f58138 ((wq_completion)loop3){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc900055dfc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc900055dfc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff8880254b2160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#2: ffff8880254b2160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953
2 locks held by getty/5558:
#0: ffff8880375ff0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:4/5812:
#0: ffff88805e5de938 ((wq_completion)hci2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff88805e5de938 ((wq_completion)hci2){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc90004c07c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc90004c07c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff88806125cf80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331
1 lock held by udevd/5817:
#0: ffff88802251d8b0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff88802251d8b0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
4 locks held by syz.5.334/8498:
#0: ffff888064082480 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88806070c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff88806070c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: open_last_lookups fs/namei.c:4586 [inline]
#1: ffff88806070c9f8 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4833
#2: ffff88806070c628 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_create+0x22e/0xb10 fs/jfs/namei.c:101
#3: ffff8880413d6d28 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_create+0x249/0xb10 fs/jfs/namei.c:102
2 locks held by syz.7.337/8501:
#0: ffff8880640820d0 (&type->s_umount_key#72){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880640820d0 (&type->s_umount_key#72){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff8880255188c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#1: ffff8880255188c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xc30 fs/fs-writeback.c:2940
4 locks held by kworker/u8:9/8851:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc9000548fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc9000548fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff8880552908b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6441 [inline]
#2: ffff8880552908b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x4a0 net/wireless/core.c:426
#3: ffff8880b8829400 ((lock)#3){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff8880b8829400 ((lock)#3){+.+.}-{3:3}, at: kcov_remote_start+0xe0/0x710 kernel/kcov.c:877
2 locks held by kworker/u8:11/8852:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc900053cfc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc900053cfc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
1 lock held by syz-executor/8882:
2 locks held by syz.4.449/9770:
#0: ffff8880640820d0 (&type->s_umount_key#72){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880640820d0 (&type->s_umount_key#72){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff8880255188c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#1: ffff8880255188c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xc30 fs/fs-writeback.c:2940
7 locks held by kworker/u8:17/10407:
4 locks held by syz.9.559/10878:
#0: ffff8880227b9c50 (&bdev->bd_fsfreeze_mutex){+.+.}-{4:4}, at: bdev_freeze+0x2a/0x220 block/bdev.c:305
#1: ffff88803841e480 (sb_writers#4){++++}-{0:0}, at: sb_wait_write fs/super.c:1850 [inline]
#1: ffff88803841e480 (sb_writers#4){++++}-{0:0}, at: freeze_super+0x535/0x1190 fs/super.c:2114
#2: ffff88803841e0d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#2: ffff88803841e0d0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#2: ffff88803841e0d0 (&type->s_umount_key#32){++++}-{4:4}, at: freeze_super+0x53d/0x1190 fs/super.c:2115
#3: ffff88803841e5f8 (sb_pagefaults){++++}-{0:0}, at: sb_wait_write fs/super.c:1850 [inline]
#3: ffff88803841e5f8 (sb_pagefaults){++++}-{0:0}, at: freeze_super+0x564/0x1190 fs/super.c:2119
1 lock held by syz.9.559/10882:
#0: ffff88803841e480 (sb_writers#4){++++}-{0:0}, at: do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
#0: ffff88803841e480 (sb_writers#4){++++}-{0:0}, at: do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
5 locks held by syz.3.561/10862:
#0: ffff88803432ebc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#2: ffff888031458298 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff888031458298 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
5 locks held by syz.3.561/10863:
#0: ffff888024511128 (&osb->obs_trim_fs_mutex){+.+.}-{4:4}, at: ocfs2_trim_fs_lock_res_init+0x25/0xa0 fs/ocfs2/dlmglue.c:703
#1: ffff888067b00b80 (&ocfs2_sysfile_lock_key[GLOBAL_BITMAP_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff888067b00b80 (&ocfs2_sysfile_lock_key[GLOBAL_BITMAP_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_trim_mainbm fs/ocfs2/alloc.c:7585 [inline]
#1: ffff888067b00b80 (&ocfs2_sysfile_lock_key[GLOBAL_BITMAP_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_trim_fs+0x65b/0x2530 fs/ocfs2/alloc.c:7723
#2: ffff888067b00978 (&oi->ip_io_mutex){+.+.}-{4:4}, at: ocfs2_read_blocks+0x1ed/0x15e0 fs/ocfs2/buffer_head_io.c:233
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: blk_mq_dispatch_queue_requests+0x552/0x800 block/blk-mq.c:2908
#4: ffff8880254b2160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
#4: ffff8880254b2160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_work drivers/block/loop.c:803 [inline]
#4: ffff8880254b2160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_queue_rq+0x23c/0xb00 drivers/block/loop.c:1889
1 lock held by syz.8.562/10868:
#0: ffff88806773a0d0 (&type->s_umount_key#68/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
2 locks held by udevd/10871:
2 locks held by syz.6.563/10874:
7 locks held by syz-executor/10888:
#0: ffff88805da49e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#1: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:288
#2: ffff88803331df58 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffff88803331df58 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:402
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#4: ffff8880b8933e90 ((lock)#2){+.+.}-{3:3}, at: __folio_batch_add_and_move+0x283/0xa90 mm/swap.c:-1
#5: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#5: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#5: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#5: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#6: ffff88806082e7f0 (&lruvec->lru_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#6: ffff88806082e7f0 (&lruvec->lru_lock){+.+.}-{3:3}, at: folio_lruvec_lock_irqsave+0x21e/0x3c0 mm/memcontrol.c:1274
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:436
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401
Code: e8 ae f5 93 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ef 19 fa fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 5a 82 f7 05 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001679d0 EFLAGS: 00000202
RAX: 1ffffffff332bb20 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff9995dd10 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff85308fc0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9995da80 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3a71042000 CR3: 000000003907a000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1970
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3272 [inline]
serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3357
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245