INFO: task kworker/u4:11:4355 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:11 state:D stack:22008 pid:4355 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747 jfs_commit_inode+0x1cb/0x520 fs/jfs/inode.c:108 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138 write_inode fs/fs-writeback.c:1483 [inline] __writeback_single_inode+0x705/0xec0 fs/fs-writeback.c:1700 writeback_sb_inodes+0x7cd/0xf50 fs/fs-writeback.c:1926 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:1997 wb_writeback+0x47e/0xbf0 fs/fs-writeback.c:2107 wb_check_background_flush fs/fs-writeback.c:2177 [inline] wb_do_writeback fs/fs-writeback.c:2265 [inline] wb_workfn+0xb8e/0xe60 fs/fs-writeback.c:2292 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INFO: task syz.2.4024:26615 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.4024 state:D stack:25104 pid:26615 ppid:25468 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 io_schedule+0x80/0xd0 kernel/sched/core.c:9023 __lock_metapage fs/jfs/jfs_metapage.c:50 [inline] lock_metapage+0x1f9/0x320 fs/jfs/jfs_metapage.c:64 __get_metapage+0x4ca/0xfa0 fs/jfs/jfs_metapage.c:639 xtSplitPage+0x26b/0x2180 fs/jfs/jfs_xtree.c:974 xtSplitUp+0x349/0x1f70 fs/jfs/jfs_xtree.c:771 xtInsert+0x41b/0xe70 fs/jfs/jfs_xtree.c:593 extAlloc+0xa23/0xf90 fs/jfs/jfs_extent.c:145 jfs_get_block+0x359/0xad0 fs/jfs/inode.c:254 __block_write_begin_int+0x57f/0x1af0 fs/buffer.c:2124 __block_write_begin fs/buffer.c:2173 [inline] block_write_begin+0x9a/0x1e0 fs/buffer.c:2234 jfs_write_begin+0x35/0x70 fs/jfs/inode.c:305 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4031 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4152 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x46c/0x990 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x19b/0x230 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8448f9bf79 RSP: 002b:00007f8449e82028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f8449215fa0 RCX: 00007f8448f9bf79 RDX: 00000000200000c1 RSI: 00002000000000c0 RDI: 0000000000000004 RBP: 00007f84490327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000009000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8449216038 R14: 00007f8449215fa0 R15: 00007fffbccebbb8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:4/59: 4 locks held by kworker/u4:11/4355: #0: ffff888017cf8538 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017cf8538 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #1: ffffc9000edf7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000edf7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2711 #2: ffff88805186a0e0 (&type->s_umount_key#121){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 #3: ffff88805c0ab948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1cb/0x520 fs/jfs/inode.c:108 1 lock held by syslogd/5122: 2 locks held by getty/5535: #0: ffff88802d52d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 4 locks held by syz.2.4024/26615: #0: ffff88805186a418 (sb_writers#35){.+.+}-{0:0}, at: vfs_write+0x21b/0x990 fs/read_write.c:580 #1: ffff88805c0abd10 (&sb->s_type->i_mutex_key#39){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff88805c0abd10 (&sb->s_type->i_mutex_key#39){+.+.}-{3:3}, at: generic_file_write_iter+0x83/0x2e0 mm/filemap.c:4149 #2: ffff88805c0ab8b8 (&jfs_ip->rdwrlock#2){+.+.}-{3:3}, at: jfs_get_block+0x154/0xad0 fs/jfs/inode.c:219 #3: ffff88805c0ab948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: extAlloc+0x109/0xf90 fs/jfs/jfs_extent.c:81 4 locks held by dhcpcd-run-hook/28544: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1093 Comm: kworker/u4:7 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:ieee80211_sta_get_rates+0x3d4/0x6b0 net/mac80211/util.c:2318 Code: e8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 84 c0 0f 85 b6 00 00 00 0f b7 6d 00 03 6c 24 38 8b 4c 24 2c d3 ed <89> ef 44 89 ee e8 42 f4 81 f7 44 39 ed 75 3e bf 40 00 00 00 89 de RSP: 0018:ffffc900044df778 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000000000 RDX: ffff888023a21e00 RSI: 00000000ffffffff RDI: 00000000ffffffff RBP: 00000000000000b4 R08: ffffffff8e8add6f R09: 1ffffffff1d15bad R10: dffffc0000000000 R11: fffffbfff1d15bae R12: 000000000000000b R13: 00000000000000b4 R14: dffffc0000000000 R15: ffff888063b8b350 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557b39ef9138 CR3: 00000000776a4000 CR4: 00000000003506e0 Call Trace: ieee80211_update_sta_info net/mac80211/ibss.c:1007 [inline] ieee80211_rx_bss_info net/mac80211/ibss.c:1122 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x10db/0x2c80 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1655 [inline] ieee80211_iface_work+0x717/0xc70 net/mac80211/iface.c:1709 cfg80211_wiphy_work+0x225/0x260 net/wireless/core.c:437 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293