INFO: task kworker/u8:10:2205 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:10 state:D stack:23080 pid:2205 tgid:2205 ppid:2 task_flags:0x4248160 flags:0x00080000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit_lock+0x115/0x1a0 kernel/sched/wait_bit.c:93 out_of_line_wait_on_bit_lock+0xd9/0x110 kernel/sched/wait_bit.c:120 wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline] __lock_buffer+0x67/0x70 fs/buffer.c:71 lock_buffer include/linux/buffer_head.h:432 [inline] do_get_write_access+0x8a0/0x12f0 fs/jbd2/transaction.c:968 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1242 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_mb_mark_context+0x175/0xda0 fs/ext4/mballoc.c:4103 ext4_mb_mark_diskspace_used+0x466/0x8c0 fs/ext4/mballoc.c:4233 ext4_mb_new_blocks+0xa31/0x4da0 fs/ext4/mballoc.c:6335 ext4_ext_map_blocks+0x1c3f/0x5f10 fs/ext4/extents.c:4383 ext4_map_create_blocks fs/ext4/inode.c:613 [inline] ext4_map_blocks+0x573/0x1350 fs/ext4/inode.c:816 mpage_map_one_extent fs/ext4/inode.c:2380 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2474 [inline] ext4_do_writepages+0x1fa9/0x3c80 fs/ext4/inode.c:2932 ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:3026 do_writepages+0x27a/0x600 mm/page-writeback.c:2598 __writeback_single_inode+0x168/0x14a0 fs/fs-writeback.c:1737 writeback_sb_inodes+0x72e/0x1ce0 fs/fs-writeback.c:2030 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2107 wb_writeback+0x799/0xae0 fs/fs-writeback.c:2218 wb_check_old_data_flush fs/fs-writeback.c:2322 [inline] wb_do_writeback fs/fs-writeback.c:2375 [inline] wb_workfn+0x8a0/0xbb0 fs/fs-writeback.c:2403 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task jbd2/sda1-8:5161 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:26504 pid:5161 tgid:5161 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] __wait_on_buffer+0x64/0x70 fs/buffer.c:123 wait_on_buffer include/linux/buffer_head.h:420 [inline] jbd2_journal_commit_transaction+0x37d3/0x67f0 fs/jbd2/commit.c:808 kjournald2+0x1f4/0x760 fs/jbd2/journal.c:201 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task syz-executor:5816 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22824 pid:5816 tgid:5816 ppid:5815 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x910/0x12f0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1242 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x340 fs/ext4/inode.c:6290 __ext4_mark_inode_dirty+0x197/0x840 fs/ext4/inode.c:6465 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6502 __mark_inode_dirty+0x1f7/0x1670 fs/fs-writeback.c:2587 generic_update_time+0xcf/0xf0 fs/inode.c:2158 inode_update_time fs/inode.c:2171 [inline] file_update_time_flags+0x410/0x520 fs/inode.c:2398 ext4_page_mkwrite+0x33d/0x1880 fs/ext4/inode.c:6668 do_page_mkwrite+0x174/0x380 mm/memory.c:3528 wp_page_shared mm/memory.c:3929 [inline] do_wp_page+0xb5d/0x5010 mm/memory.c:4148 handle_pte_fault mm/memory.c:6289 [inline] __handle_mm_fault+0x1bd2/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7febc7469065 RSP: 002b:00007fff14a055c0 EFLAGS: 00010206 RAX: 00007febc303feec RBX: 00007fff14a056c0 RCX: 0000000000000000 RDX: 00007febc303fee8 RSI: 0000000000000008 RDI: 00007fff14a056c0 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fff14a056a0 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000114 R14: fffffffffffffeec R15: 0000000000000114 INFO: task syz.4.1186:12027 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1186 state:D stack:25032 pid:12027 tgid:12027 ppid:10034 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x910/0x12f0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1242 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x340 fs/ext4/inode.c:6290 __ext4_mark_inode_dirty+0x197/0x840 fs/ext4/inode.c:6465 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6502 __mark_inode_dirty+0x1f7/0x1670 fs/fs-writeback.c:2587 generic_update_time+0xcf/0xf0 fs/inode.c:2158 inode_update_time fs/inode.c:2171 [inline] file_update_time_flags+0x410/0x520 fs/inode.c:2398 ext4_page_mkwrite+0x33d/0x1880 fs/ext4/inode.c:6668 do_page_mkwrite+0x174/0x380 mm/memory.c:3528 do_shared_fault mm/memory.c:5831 [inline] do_fault+0x3fc/0x1ad0 mm/memory.c:5893 do_pte_missing mm/memory.c:4401 [inline] handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f0404c6f922 RSP: 002b:00007ffe37b87090 EFLAGS: 00010202 RAX: 0000000000050008 RBX: 00007f0405b15720 RCX: 0000000000000000 RDX: 0000001b2fdd4000 RSI: 0000000000000008 RDI: 00007f0405b15720 RBP: 0000000000000100 R08: 00007f04047ff080 R09: 00007f0404fd2000 R10: 00007f04047ff008 R11: 0000000000000012 R12: ffffffff819c34a1 R13: 00007f0404fe6038 R14: 00000000000000f6 R15: fffffffffffb0000 INFO: task syz.3.1188:12040 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.1188 state:D stack:26664 pid:12040 tgid:12040 ppid:5828 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x910/0x12f0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1242 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x340 fs/ext4/inode.c:6290 __ext4_mark_inode_dirty+0x197/0x840 fs/ext4/inode.c:6465 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6502 __mark_inode_dirty+0x1f7/0x1670 fs/fs-writeback.c:2587 generic_update_time+0xcf/0xf0 fs/inode.c:2158 inode_update_time fs/inode.c:2171 [inline] file_update_time_flags+0x410/0x520 fs/inode.c:2398 ext4_page_mkwrite+0x33d/0x1880 fs/ext4/inode.c:6668 do_page_mkwrite+0x174/0x380 mm/memory.c:3528 do_shared_fault mm/memory.c:5831 [inline] do_fault+0x3fc/0x1ad0 mm/memory.c:5893 do_pte_missing mm/memory.c:4401 [inline] handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fd1c366f922 RSP: 002b:00007ffd2fd5b190 EFLAGS: 00010202 RAX: 0000000000037008 RBX: 00007fd1c4515720 RCX: 0000000000000000 RDX: 0000001b313ed000 RSI: 0000000000000008 RDI: 00007fd1c4515720 RBP: 00000000000008f8 R08: 00007fd1c2df5058 R09: 00007fd1c39d2000 R10: 00007fd1c2df5008 R11: 000000000000000f R12: ffffffff8b6efcda R13: 00007fd1c39e6128 R14: 00000000000000c8 R15: fffffffffffc9000 INFO: task syz.0.1190:12050 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1190 state:D stack:26664 pid:12050 tgid:12050 ppid:5831 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 io_schedule+0xbf/0x130 kernel/sched/core.c:7789 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x910/0x12f0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1242 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x340 fs/ext4/inode.c:6290 __ext4_mark_inode_dirty+0x197/0x840 fs/ext4/inode.c:6465 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6502 __mark_inode_dirty+0x1f7/0x1670 fs/fs-writeback.c:2587 generic_update_time+0xcf/0xf0 fs/inode.c:2158 inode_update_time fs/inode.c:2171 [inline] file_update_time_flags+0x410/0x520 fs/inode.c:2398 ext4_page_mkwrite+0x33d/0x1880 fs/ext4/inode.c:6668 do_page_mkwrite+0x174/0x380 mm/memory.c:3528 do_shared_fault mm/memory.c:5831 [inline] do_fault+0x3fc/0x1ad0 mm/memory.c:5893 do_pte_missing mm/memory.c:4401 [inline] handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f18e8c6f17a RSP: 002b:00007fff6aaaa6d0 EFLAGS: 00010202 RAX: 0000001b30f1d000 RBX: 00007f18e9b15720 RCX: 0000001b30f1cff8 RDX: 0000001b30b24220 RSI: 0000000000000008 RDI: 00007f18e9b15720 RBP: ffffffff824ded2f R08: 00007f18e8fe6038 R09: 00007f18e8fd2000 R10: 00007f18e87ff008 R11: 0000000000000001 R12: 0000000000000001 R13: 00000000000001ef R14: ffffffff824de6d8 R15: 0000000000000377 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 6 locks held by kworker/u8:10/2205: #0: ffff888141ed1948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc900052b7c90 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffff8880347580e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:563 #3: ffff88803475ab98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x27a/0x600 mm/page-writeback.c:2598 #4: ffff88803475c950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444 #5: ffff888076e28270 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x475/0x1350 fs/ext4/inode.c:815 2 locks held by getty/5585: #0: ffff88803541d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/5816: #0: ffff88807763fd08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x580 mm/mmap_lock.c:259 #1: ffff888034758518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3528 #2: ffff88803475c950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444 3 locks held by kworker/0:3H/7535: #0: ffff88801bef1548 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232 #1: ffffc90005297c90 ((work_completion)(&q->timeout_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233 #2: ffffffff8e3d4c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 3 locks held by syz.4.1186/12027: #0: ffff8880773a7308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x580 mm/mmap_lock.c:259 #1: ffff888034758518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3528 #2: ffff88803475c950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444 3 locks held by syz.3.1188/12040: #0: ffff88806a409e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x580 mm/mmap_lock.c:259 #1: ffff888034758518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3528 #2: ffff88803475c950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444 3 locks held by syz.0.1190/12050: #0: ffff888069cae808 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x580 mm/mmap_lock.c:259 #1: ffff888034758518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3528 #2: ffff88803475c950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:160 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x133/0x180 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xe66/0x1180 kernel/hung_task.c:515 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246