INFO: task kworker/0:9:4331 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:9 state:D stack:23832 pid:4331 ppid:2 flags:0x00004000 Workqueue: gfs_recovery gfs2_recover_func Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 io_schedule+0x7c/0xd0 kernel/sched/core.c:8798 folio_wait_bit_common+0x70a/0xfa0 mm/filemap.c:1324 folio_wait_locked include/linux/pagemap.h:1059 [inline] gfs2_jhead_process_page+0x17a/0x800 fs/gfs2/lops.c:476 gfs2_find_jhead+0xba2/0xd00 fs/gfs2/lops.c:594 gfs2_recover_func+0x6d2/0x1ca0 fs/gfs2/recovery.c:460 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz.0.17:4431 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:24784 pid:4431 ppid:4387 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 bit_wait+0xd/0xc0 kernel/sched/wait_bit.c:199 __wait_on_bit+0xa8/0x2d0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] gfs2_recover_journal+0xd6/0x130 fs/gfs2/recovery.c:577 init_journal+0x17fc/0x23e0 fs/gfs2/ops_fstype.c:835 init_inodes+0xdb/0x320 fs/gfs2/ops_fstype.c:889 gfs2_fill_super+0x1749/0x1fb0 fs/gfs2/ops_fstype.c:1246 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1327 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4e7519e04a RSP: 002b:00007ffc20c44a18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ffc20c44aa0 RCX: 00007f4e7519e04a RDX: 0000200000037f40 RSI: 00002000000008c0 RDI: 00007ffc20c44a60 RBP: 0000200000037f40 R08: 00007ffc20c44aa0 R09: 0000000001010084 R10: 0000000001010084 R11: 0000000000000246 R12: 00002000000008c0 R13: 00007ffc20c44a60 R14: 0000000000037f45 R15: 0000200000000480 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2e790 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4022: #0: ffff88814d2c5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198 2 locks held by kworker/0:9/4331: #0: ffff88801af99938 ((wq_completion)gfs_recovery){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003f77d00 ((work_completion)(&jd->jd_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 2 locks held by kworker/u4:5/4377: 1 lock held by syz.0.17/4431: #0: ffff88807a7560e0 (&type->s_umount_key#52/1){+.+.}-{3:3}, at: alloc_super+0x1fa/0x930 fs/super.c:228 2 locks held by syz.1.215/4659: 2 locks held by dhcpcd/4660: #0: ffff888147b20130 ( sk_lock-AF_PACKET ){+.+.}-{0:0} , at: lock_sock include/net/sock.h:1805 [inline] , at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249 #1: ffffffff8cb332b8 (rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] , at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline] RIP: 0010:unwind_next_frame+0x132e/0x20b0 arch/x86/kernel/unwind_orc.c:448 Code: 00 c6 05 56 5b d2 0c 01 48 c7 c7 40 83 89 8a 48 8b 74 24 68 e8 75 94 e9 08 e9 7f 05 00 00 49 89 f7 49 89 f5 4c 89 e0 4c 29 e8 <48> 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4d 8d 74 45 RSP: 0018:ffffc900001075b0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc90000107688 RCX: ffffffff96c00100 RDX: ffffffff8ef1ef72 RSI: ffffffff8e66b0ec RDI: 0000000000000001 RBP: ffffffff86138c8e R08: 0000000000000001 R09: 0000000000000005 R10: dffffc0000000000 R11: fffff52000020edd R12: ffffffff8e66b0ec R13: ffffffff8e66b0ec R14: 000000000005138c R15: ffffffff8e66b0ec FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f75987e2000 CR3: 0000000072b7a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] kmem_cache_alloc_node+0x14d/0x320 mm/slub.c:3404 __alloc_skb+0xfc/0x7e0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1303 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x28f/0xaf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295