INFO: task syz-executor:4173 blocked 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:22864 pid: 4173 ppid: 4172 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x134/0xe40 fs/jbd2/transaction.c:1116 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1251 __ext4_journal_get_write_access+0x24d/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x203/0x2e0 fs/ext4/inode.c:5866 __ext4_mark_inode_dirty+0x13b/0x6c0 fs/ext4/inode.c:6050 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6087 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480 generic_update_time+0x1cd/0x1f0 fs/inode.c:1881 inode_update_time fs/inode.c:1894 [inline] file_update_time+0x3c0/0x440 fs/inode.c:2083 ext4_page_mkwrite+0x1bc/0x1250 fs/ext4/inode.c:6205 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 wp_page_shared+0x163/0x6c0 mm/memory.c:3259 handle_pte_fault mm/memory.c:4668 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1fbd/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7feaab6e80c3 RSP: 002b:00007ffc815bce20 EFLAGS: 00010206 RAX: 00007feaa6672000 RBX: 00007ffc815bcf50 RCX: 0000000000000004 RDX: 00007feaa6671ff8 RSI: 0000000000000008 RDI: 00007ffc815bcf50 RBP: 0000000086e2a3c0 R08: 0000000086e2a3c0 R09: 0000000000000041 R10: 00007ffc815bcf30 R11: 0000000000000000 R12: 0000000000004ff8 R13: 0000000000004ffc R14: 0000000000000000 R15: 0000000000005008 INFO: task syz.6.280:5235 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.280 state:D stack:27200 pid: 5235 ppid: 4421 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x134/0xe40 fs/jbd2/transaction.c:1116 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1251 __ext4_journal_get_write_access+0x24d/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x203/0x2e0 fs/ext4/inode.c:5866 __ext4_mark_inode_dirty+0x13b/0x6c0 fs/ext4/inode.c:6050 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6087 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480 generic_update_time+0x1cd/0x1f0 fs/inode.c:1881 inode_update_time fs/inode.c:1894 [inline] file_update_time+0x3c0/0x440 fs/inode.c:2083 ext4_page_mkwrite+0x1bc/0x1250 fs/ext4/inode.c:6205 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 do_shared_fault mm/memory.c:4328 [inline] do_fault mm/memory.c:4396 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1e47/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f236444d889 RSP: 002b:00007ffd3c4edcd0 EFLAGS: 00010202 RAX: 0000001b30824000 RBX: 0000000000000000 RCX: 00000000005ffde8 RDX: 0000001b30823ffc RSI: 00000000005ffde8 RDI: 00007f2365330700 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f23647ed000 R10: 00007f2365330700 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000074ba R14: ffffffff817ca2f4 R15: 00007f2365330720 INFO: task syz.5.281:5236 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.281 state:D stack:27200 pid: 5236 ppid: 4360 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x134/0xe40 fs/jbd2/transaction.c:1116 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1251 __ext4_journal_get_write_access+0x24d/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x203/0x2e0 fs/ext4/inode.c:5866 __ext4_mark_inode_dirty+0x13b/0x6c0 fs/ext4/inode.c:6050 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6087 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480 generic_update_time+0x1cd/0x1f0 fs/inode.c:1881 inode_update_time fs/inode.c:1894 [inline] file_update_time+0x3c0/0x440 fs/inode.c:2083 ext4_page_mkwrite+0x1bc/0x1250 fs/ext4/inode.c:6205 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 do_shared_fault mm/memory.c:4328 [inline] do_fault mm/memory.c:4396 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1e47/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f0278bfa829 RSP: 002b:00007ffc54e89300 EFLAGS: 00010202 RAX: 0000001b34a24000 RBX: ffffffff87b57c31 RCX: 0000001b34a23ff8 RDX: 00000000005ffde8 RSI: 00000000005ffde8 RDI: 00007f0279add700 RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f0278f9a000 R10: 00007f0279add700 R11: 0000000000000000 R12: 00007f0278fae038 R13: 0000000000005b75 R14: ffffffff87b573b2 R15: 00007f0279add720 INFO: task syz.0.282:5240 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.282 state:D stack:27200 pid: 5240 ppid: 4187 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11c3/0x4350 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0x173/0x230 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x134/0xe40 fs/jbd2/transaction.c:1116 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1251 __ext4_journal_get_write_access+0x24d/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x203/0x2e0 fs/ext4/inode.c:5866 __ext4_mark_inode_dirty+0x13b/0x6c0 fs/ext4/inode.c:6050 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6087 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480 generic_update_time+0x1cd/0x1f0 fs/inode.c:1881 inode_update_time fs/inode.c:1894 [inline] file_update_time+0x3c0/0x440 fs/inode.c:2083 ext4_page_mkwrite+0x1bc/0x1250 fs/ext4/inode.c:6205 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 do_shared_fault mm/memory.c:4328 [inline] do_fault mm/memory.c:4396 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1e47/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f4836bd6b23 RSP: 002b:00007ffe10cb0fe0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b32064000 RDX: 0000001b32024000 RSI: 0000000000600000 RDI: 00007f4836f4d708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe10cb1270 Showing all locks held in the system: 2 locks held by kworker/1:0/21: 1 lock held by khungtaskd/27: #0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3944: #0: ffff88814ca96098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158 3 locks held by syz-executor/4173: #0: ffff88807a7a6328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807a7a6328 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296 #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1817 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1916 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1a5/0x1250 fs/ext4/inode.c:6204 #2: ffff88814cfc0990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x12d5/0x1560 fs/jbd2/transaction.c:462 3 locks held by kworker/u4:7/4661: 2 locks held by kworker/1:11/4676: #0: ffff888017872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1 #1: ffffc90003447d00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285 3 locks held by syz.6.280/5235: #0: ffff88802506ea28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88802506ea28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296 #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1817 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1916 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1a5/0x1250 fs/ext4/inode.c:6204 #2: ffff88814cfc0990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x12d5/0x1560 fs/jbd2/transaction.c:462 3 locks held by syz.5.281/5236: #0: ffff88807a297828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807a297828 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296 #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1817 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1916 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1a5/0x1250 fs/ext4/inode.c:6204 #2: ffff88814cfc0990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x12d5/0x1560 fs/jbd2/transaction.c:462 3 locks held by syz.0.282/5240: #0: ffff88802506a428 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88802506a428 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296 #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1817 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1916 [inline] #1: ffff88802cff4558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1a5/0x1250 fs/ext4/inode.c:6204 #2: ffff88814cfc0990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x12d5/0x1560 fs/jbd2/transaction.c:462 2 locks held by dhcpcd/5624: #0: ffff8880727da010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline] #0: ffff8880727da010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline] #0: ffff8880727da010 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1346 #1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe1b/0xe60 kernel/hung_task.c:369 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4661 Comm: kworker/u4:7 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:check_kcov_mode kernel/kcov.c:171 [inline] RIP: 0010:write_comp_data kernel/kcov.c:226 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0x69/0xe0 kernel/kcov.c:328 Code: 4c 09 01 48 8b 54 24 20 65 4c 8b 05 b1 47 89 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 9f 47 89 7e <41> 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 34 RSP: 0018:ffffc90003407598 EFLAGS: 00000016 RAX: 0000000000000020 RBX: 00000050b81e5a34 RCX: 0000000000000005 RDX: ffffffff817c150d RSI: ffffffff8d1605e0 RDI: 0000000000000009 RBP: 0000000000000009 R08: ffff8880216b9dc0 R09: 000000000000001d R10: 000000000000001d R11: 0000000080000005 R12: ffff888019bb3308 R13: dffffc0000000000 R14: 00000000000002f8 R15: 0000000000021849 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557d8b23a168 CR3: 000000007dc59000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_buffer+0x23d/0x880 kernel/trace/ring_buffer.c:3452 __rb_reserve_next+0x4d9/0xd00 kernel/trace/ring_buffer.c:3581 rb_reserve_next_event kernel/trace/ring_buffer.c:3716 [inline] ring_buffer_lock_reserve+0xadd/0xed0 kernel/trace/ring_buffer.c:3775 __trace_buffer_lock_reserve kernel/trace/trace.c:942 [inline] trace_event_buffer_lock_reserve+0xd4/0x6a0 kernel/trace/trace.c:2819 trace_event_buffer_reserve+0x2a8/0x3d0 kernel/trace/trace_events.c:627 trace_event_raw_event_lock_acquire+0x158/0x2b0 include/trace/events/lock.h:13 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x3d7/0x400 kernel/locking/lockdep.c:5708 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 try_to_wake_up+0x5a/0x1020 kernel/sched/core.c:4049 wake_up_worker kernel/workqueue.c:859 [inline] process_one_work+0x693/0xff0 kernel/workqueue.c:2273 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287