INFO: task kworker/u8:8:1163 blocked for more than 144 seconds. Not tainted 6.13.0-syzkaller-00603-g3d3a9c8b89d4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:8 state:D stack:23696 pid:1163 tgid:1163 ppid:2 flags:0x00004000 Workqueue: events_unbound netfs_write_collection_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 bit_wait+0x15/0xe0 kernel/sched/wait_bit.c:237 __wait_on_bit+0x62/0x180 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0xda/0x110 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:77 [inline] netfs_retry_writes+0x2fa/0x1a00 fs/netfs/write_retry.c:215 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline] netfs_write_collection_worker+0x23de/0x37c0 fs/netfs/write_collect.c:374 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.2.1761:12416 blocked for more than 145 seconds. Not tainted 6.13.0-syzkaller-00603-g3d3a9c8b89d4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1761 state:D stack:26032 pid:12416 tgid:12415 ppid:5814 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x62b/0xa60 kernel/locking/mutex.c:735 netfs_writepages+0x16c/0x8f0 fs/netfs/write_issue.c:564 do_writepages+0x1b3/0x820 mm/page-writeback.c:2708 filemap_fdatawrite_wbc mm/filemap.c:388 [inline] filemap_fdatawrite_wbc+0x104/0x160 mm/filemap.c:378 __filemap_fdatawrite_range+0xb3/0xf0 mm/filemap.c:421 v9fs_dir_release+0x429/0x590 fs/9p/vfs_dir.c:219 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 get_signal+0x1d3/0x26c0 kernel/signal.c:2809 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7effc0585d29 RSP: 002b:00007effc136b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: 0000000000220000 RBX: 00007effc0775fa0 RCX: 00007effc0585d29 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 00007effc0601b08 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007effc0775fa0 R15: 00007fff5bc84908 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e1bbcc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bbcc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bbcc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 2 locks held by kworker/u8:4/72: #0: ffff88801f362948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000214fd80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 2 locks held by kworker/u8:8/1163: #0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000406fd80 ((work_completion)(&rreq->work)#2){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 1 lock held by syslogd/5173: 2 locks held by getty/5579: #0: ffff88814d62c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:17/6444: #0: ffff88801f362948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000ca87d80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 1 lock held by syz.1.1748/12372: #0: ffff88805baf11e0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xb9/0x8f0 fs/netfs/write_issue.c:558 1 lock held by syz.2.1761/12416: #0: ffff88805bb19ec0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0x16c/0x8f0 fs/netfs/write_issue.c:564 3 locks held by syz.2.1761/12418: #0: ffff88805cc04420 (sb_writers#15){.+.+}-{0:0}, at: vfs_utimes+0x6b9/0x850 fs/utimes.c:36 #1: ffff88805bb19b08 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: inode_lock include/linux/fs.h:831 [inline] #1: ffff88805bb19b08 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: vfs_utimes+0x3d2/0x850 fs/utimes.c:65 #2: ffff88805bb19ec0 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xb9/0x8f0 fs/netfs/write_issue.c:558 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-00603-g3d3a9c8b89d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 72 Comm: kworker/u8:4 Not tainted 6.13.0-syzkaller-00603-g3d3a9c8b89d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:unwind_next_frame+0x4d0/0x20c0 arch/x86/kernel/unwind_orc.c:505 Code: e8 55 f1 ff ff 48 85 c0 48 89 c1 0f 84 13 fe ff ff 4c 8d 79 05 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 0f b6 04 02 <4c> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 d8 13 00 00 0f b6 41 05 RSP: 0018:ffffc9000214f768 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff910166d0 RDX: 1ffffffff2202cda RSI: 0000000000000000 RDI: ffffffff907aa6d0 RBP: ffffc9000214f820 R08: ffffffff9101671e R09: ffffffff90f82ba6 R10: ffffc9000214f7d8 R11: 000000000000fcb0 R12: ffffc9000214f828 R13: ffffc9000214f7d8 R14: ffffc9000214f80d R15: ffffffff910166d5 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000b000 CR3: 000000007c340000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4613 [inline] kmem_cache_free+0x152/0x4c0 mm/slub.c:4715 kfree_skbmem+0x1a4/0x1f0 net/core/skbuff.c:1148 __kfree_skb net/core/skbuff.c:1205 [inline] sk_skb_reason_drop+0x136/0x1a0 net/core/skbuff.c:1242 kfree_skb_reason include/linux/skbuff.h:1263 [inline] kfree_skb include/linux/skbuff.h:1272 [inline] ieee80211_iface_work+0x437/0xf00 net/mac80211/iface.c:1669 cfg80211_wiphy_work+0x3de/0x560 net/wireless/core.c:440 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 vkms_vblank_simulate: vblank timer overrun