INFO: task syz-executor:5592 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22208 pid:5592 tgid:5592 ppid:5591 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5535 [inline] __schedule+0x1b47/0x5c60 kernel/sched/core.c:7305 __schedule_loop kernel/sched/core.c:7382 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7397 io_schedule+0x7f/0xd0 kernel/sched/core.c:8069 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258 __wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:106 [inline] do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x141/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2744 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2483 ext4_page_mkwrite+0x21f/0x12c0 fs/ext4/inode.c:6902 do_page_mkwrite+0x147/0x310 mm/memory.c:3878 wp_page_shared mm/memory.c:4279 [inline] do_wp_page+0x1a85/0x4b60 mm/memory.c:4502 handle_pte_fault mm/memory.c:6650 [inline] __handle_mm_fault mm/memory.c:6775 [inline] handle_mm_fault+0x15d7/0x3750 mm/memory.c:6942 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fc5502701e3 RSP: 002b:00007ffe6b041840 EFLAGS: 00010216 RAX: 00007fc54c1fd204 RBX: 00007ffe6b041970 RCX: 0000000000000000 RDX: 00007fc54c1fd200 RSI: 0000000000000008 RDI: 00007ffe6b041970 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffe6b041950 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000002dfc R14: ffffffffffffd204 R15: 0000000000000000 INFO: task syz.2.124:6395 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.124 state:D stack:26024 pid:6395 tgid:6395 ppid:5604 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5535 [inline] __schedule+0x1b47/0x5c60 kernel/sched/core.c:7305 __schedule_loop kernel/sched/core.c:7382 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7397 io_schedule+0x7f/0xd0 kernel/sched/core.c:8069 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258 __wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:106 [inline] do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x141/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2744 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2483 ext4_page_mkwrite+0x21f/0x12c0 fs/ext4/inode.c:6902 do_page_mkwrite+0x147/0x310 mm/memory.c:3878 do_shared_fault mm/memory.c:6144 [inline] do_fault mm/memory.c:6206 [inline] do_pte_missing+0x70f/0x3570 mm/memory.c:4762 handle_pte_fault mm/memory.c:6626 [inline] __handle_mm_fault mm/memory.c:6775 [inline] handle_mm_fault+0x1a53/0x3750 mm/memory.c:6942 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7fe259672809 RSP: 002b:00007ffc7f258980 EFLAGS: 00010202 RAX: 0000001b32f24000 RBX: 0000000000000000 RCX: 00000000003ffde8 RDX: 0000001b32f23ffc RSI: 00000000003ffde8 RDI: 00007fe25a555700 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fe259a12000 R10: 00007fe25a555700 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000007a5 R14: ffffffff816d729e R15: 00007fe25a555720 Showing all locks held in the system: locks held by khungtaskd/34: 1, last CPU#0: #0: ffffffff8ed5c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ed5c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ed5c2a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:2/45: 6, on CPU#0: #0: ffff88801ee92948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801ee92948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801ee92948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #0: ffff88801ee92948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #1: ffffc90000b57c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #2: ffff88803651c0e8 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:670 #3: ffff88803651ac98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1f1/0x4e0 fs/ext4/inode.c:3031 #4: ffff888036518938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 #5: ffff88807706eed8 (&ei->i_data_sem#2){++++}-{4:4}, at: ext4_map_blocks+0x77d/0x12c0 fs/ext4/inode.c:822 locks held by getty/5360: 2, on CPU#1: #0: ffff888035ce60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032362e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5592: 3, on CPU#1: #0: ffff88803333ad08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:309 #1: ffff88803651c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff88803651c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fd/0x12c0 fs/ext4/inode.c:6901 #2: ffff888036518938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 locks held by syz.2.124/6395: 3, on CPU#0: #0: ffff88802903ed08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:309 #1: ffff88803651c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff88803651c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fd/0x12c0 fs/ext4/inode.c:6901 #2: ffff888036518938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:377 [inline] watchdog+0x1058/0x10d0 kernel/hung_task.c:598 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline] RIP: 0010:unwind_next_frame+0x51a/0x2550 arch/x86/kernel/unwind_orc.c:510 Code: 0f b6 04 08 84 c0 75 27 48 63 03 48 01 d8 48 8d 4b 04 48 39 e8 4c 0f 46 f9 48 8d 43 fc 4c 0f 47 e0 4c 0f 46 eb 4d 39 e7 76 a9 7c fd ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c cd 48 89 df 48 89 RSP: 0018:ffffc90000a38620 EFLAGS: 00000202 RAX: ffffffff91004f84 RBX: ffffffff91004f88 RCX: ffffffff91004f8c RDX: ffffffff91004f88 RSI: ffffffff91b5a3ca RDI: ffffffff8c6dd420 RBP: ffffffff8b6603ac R08: 0000000000000001 R09: 0000000000000000 R10: ffffc90000a38718 R11: ffffffff81b37c90 R12: ffffffff91004f88 R13: ffffffff91004f88 R14: ffffc90000a386c8 R15: ffffffff91004f8c FS: 0000000000000000(0000) GS:ffff888124db7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005561b5fe6660 CR3: 000000000eb46000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:351 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:377 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:5033 [inline] kmem_cache_alloc_node_noprof+0x34f/0x600 mm/slub.c:5105 __alloc_skb+0x1db/0x7a0 net/core/skbuff.c:704 __netdev_alloc_skb+0xc2/0x820 net/core/skbuff.c:777 netdev_alloc_skb include/linux/skbuff.h:3512 [inline] dev_alloc_skb include/linux/skbuff.h:3525 [inline] __ieee80211_beacon_get+0xcfd/0x1920 net/mac80211/tx.c:5895 ieee80211_beacon_get_tim+0xbd/0x2c0 net/mac80211/tx.c:6017 ieee80211_beacon_get include/net/mac80211.h:5901 [inline] mac80211_hwsim_beacon_tx+0x378/0x820 drivers/net/wireless/virtual/mac80211_hwsim_main.c:2505 __iterate_interfaces+0x2af/0x5a0 net/mac80211/util.c:775 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:811 mac80211_hwsim_beacon+0xaf/0x240 drivers/net/wireless/virtual/mac80211_hwsim_main.c:2541 __run_hrtimer kernel/time/hrtimer.c:2075 [inline] __hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2132 hrtimer_run_softirq+0x1e3/0x2e0 kernel/time/hrtimer.c:2149 handle_softirqs+0x223/0x840 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 7b 83 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 44 1e 00 fb f4 4c 18 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffc900001c7e40 EFLAGS: 00000246 RAX: 000000000023af09 RBX: ffffffff819c7950 RCX: 8000000000000001 RDX: 0000000000000001 RSI: ffffffff8e418b63 RDI: ffffffff8c6dd480 RBP: ffffc900001c7f10 R08: ffff8880b8733e5b R09: 1ffff110170e67cb R10: dffffc0000000000 R11: ffffed10170e67cc R12: 0000000000000000 R13: 1ffff11003cd83e8 R14: 1ffff92000038fd0 R15: dffffc0000000000 arch_safe_halt arch/x86/kernel/process.c:767 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:768 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x2e0/0x540 kernel/sched/idle.c:355 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x157