INFO: task kworker/u8:6:1095 blocked for more than 143 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:6 state:D stack:23104 pid:1095 tgid:1095 ppid:2 task_flags:0x4248060 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 io_schedule+0xbf/0x130 kernel/sched/core.c:7690 folio_wait_bit_common+0x3d8/0x9b0 mm/filemap.c:1317 folio_wait_writeback+0x3c/0x90 mm/page-writeback.c:3179 mpage_prepare_extent_to_map+0x533/0x1470 fs/ext4/inode.c:2496 ext4_do_writepages+0x968/0x32d0 fs/ext4/inode.c:2688 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2824 do_writepages+0x1b3/0x820 mm/page-writeback.c:2687 __writeback_single_inode+0x166/0xfa0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x606/0xfa0 fs/fs-writeback.c:1976 wb_writeback+0x422/0xb80 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x151/0xbc0 fs/fs-writeback.c:2343 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz-executor:5824 blocked for more than 144 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22800 pid:5824 tgid:5824 ppid:5822 task_flags:0x440100 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 io_schedule+0xbf/0x130 kernel/sched/core.c:7690 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247 __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_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x933/0x1270 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1245 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:239 ext4_reserve_inode_write+0x13b/0x270 fs/ext4/inode.c:5831 __ext4_mark_inode_dirty+0x1ab/0x860 fs/ext4/inode.c:6005 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6042 __mark_inode_dirty+0x1ec/0xe50 fs/fs-writeback.c:2515 generic_update_time+0xcf/0xf0 fs/inode.c:2112 inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2383 ext4_page_mkwrite+0x368/0x1760 fs/ext4/inode.c:6160 do_page_mkwrite+0x177/0x380 mm/memory.c:3256 wp_page_shared mm/memory.c:3657 [inline] do_wp_page+0xc4b/0x4670 mm/memory.c:3807 handle_pte_fault mm/memory.c:5904 [inline] __handle_mm_fault+0x1ade/0x2a40 mm/memory.c:6031 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6200 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f0eb3a765ef RSP: 002b:00007ffcbef5acf0 EFLAGS: 00010202 RAX: 00007f0eb2094000 RBX: 00005555636e31f0 RCX: 0000000000000003 RDX: 1ffffffff03f4e1b RSI: 00005555636ecb88 RDI: 0000000000000008 RBP: 00007ffcbef5afe0 R08: 00005555636ecec0 R09: 00000000000029c3 R10: 0000000000000001 R11: 00007ffcbef5b1f0 R12: 00007ffcbef5b040 R13: 0000000000000004 R14: 00007ffcbef5ad60 R15: 00007ffcbef5ae30 INFO: task syz.3.5193:17681 blocked for more than 144 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.5193 state:D stack:27904 pid:17681 tgid:17681 ppid:6158 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 io_schedule+0xbf/0x130 kernel/sched/core.c:7690 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247 __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_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x933/0x1270 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1245 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:239 ext4_reserve_inode_write+0x13b/0x270 fs/ext4/inode.c:5831 __ext4_mark_inode_dirty+0x1ab/0x860 fs/ext4/inode.c:6005 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6042 __mark_inode_dirty+0x1ec/0xe50 fs/fs-writeback.c:2515 generic_update_time+0xcf/0xf0 fs/inode.c:2112 inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2383 ext4_page_mkwrite+0x368/0x1760 fs/ext4/inode.c:6160 do_page_mkwrite+0x177/0x380 mm/memory.c:3256 wp_page_shared mm/memory.c:3657 [inline] do_wp_page+0xc4b/0x4670 mm/memory.c:3807 handle_pte_fault mm/memory.c:5904 [inline] __handle_mm_fault+0x1ade/0x2a40 mm/memory.c:6031 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6200 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fad8ee6d3c8 RSP: 002b:00007ffd8bbe6830 EFLAGS: 00010206 RAX: ffffffffffffe2f6 RBX: 00007fad8fcd5720 RCX: 0000001b2c21e2f0 RDX: 0000001b2be2021c RSI: 0000000000000006 RDI: 00007fad8fcd5720 RBP: ffffffff823358dc R08: 00007fad8f1a6038 R09: 00007fad8f192000 R10: 00007fad8e5ff008 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffff823351b6 R15: 0000000000000000 INFO: task syz.3.5193:17684 blocked for more than 145 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.5193 state:D stack:28128 pid:17684 tgid:17681 ppid:6158 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 wb_wait_for_completion+0x1b2/0x270 fs/fs-writeback.c:216 sync_inodes_sb+0x1b7/0xa50 fs/fs-writeback.c:2821 sync_filesystem+0x176/0x290 fs/sync.c:64 fs_bdev_sync+0x2c/0x40 fs/super.c:1435 blkdev_flushbuf block/ioctl.c:426 [inline] blkdev_common_ioctl+0x187c/0x2210 block/ioctl.c:564 blkdev_ioctl+0x1cd/0x6d0 block/ioctl.c:687 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fad8ef8d169 RSP: 002b:00007fad8feb4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fad8f1a5fa0 RCX: 00007fad8ef8d169 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007fad8f00e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fad8f1a5fa0 R15: 00007ffd8bbe67a8 INFO: task syz.1.5199:17696 blocked for more than 145 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.5199 state:D stack:27360 pid:17696 tgid:17696 ppid:6151 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 io_schedule+0xbf/0x130 kernel/sched/core.c:7690 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247 __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_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x933/0x1270 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1245 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:239 ext4_reserve_inode_write+0x13b/0x270 fs/ext4/inode.c:5831 __ext4_mark_inode_dirty+0x1ab/0x860 fs/ext4/inode.c:6005 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6042 __mark_inode_dirty+0x1ec/0xe50 fs/fs-writeback.c:2515 generic_update_time+0xcf/0xf0 fs/inode.c:2112 inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2383 ext4_page_mkwrite+0x368/0x1760 fs/ext4/inode.c:6160 do_page_mkwrite+0x177/0x380 mm/memory.c:3256 do_shared_fault mm/memory.c:5485 [inline] do_fault mm/memory.c:5547 [inline] do_pte_missing+0x29e/0x3e10 mm/memory.c:4059 handle_pte_fault mm/memory.c:5888 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:6031 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6200 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f4520a6d2fa RSP: 002b:00007ffca3ba3ec0 EFLAGS: 00010202 RAX: 0000001b2c020000 RBX: 00007f45218d5720 RCX: 0000001b2c01fff8 RDX: 00000000003ffde8 RSI: 00000000003ffde8 RDI: 00007f45218d5700 RBP: ffffffff822c9324 R08: 00007f4520da6038 R09: 00007f4520d92000 R10: 00007f45201ff008 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: ffffffff822c9a4e R15: 0000000000000001 INFO: task syz.0.5200:17698 blocked for more than 146 seconds. Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.5200 state:D stack:28080 pid:17698 tgid:17698 ppid:6149 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 io_schedule+0xbf/0x130 kernel/sched/core.c:7690 bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247 __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_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x933/0x1270 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1245 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:239 ext4_reserve_inode_write+0x13b/0x270 fs/ext4/inode.c:5831 __ext4_mark_inode_dirty+0x1ab/0x860 fs/ext4/inode.c:6005 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6042 __mark_inode_dirty+0x1ec/0xe50 fs/fs-writeback.c:2515 generic_update_time+0xcf/0xf0 fs/inode.c:2112 inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2383 ext4_page_mkwrite+0x368/0x1760 fs/ext4/inode.c:6160 do_page_mkwrite+0x177/0x380 mm/memory.c:3256 do_shared_fault mm/memory.c:5485 [inline] do_fault mm/memory.c:5547 [inline] do_pte_missing+0x29e/0x3e10 mm/memory.c:4059 handle_pte_fault mm/memory.c:5888 [inline] __handle_mm_fault+0x103c/0x2a40 mm/memory.c:6031 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6200 do_user_addr_fault+0x60d/0x13f0 arch/x86/mm/fault.c:1337 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fb6f5463c9b RSP: 002b:00007ffd8e3b57c0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b33b20000 RSI: 0000000000600000 RDI: 00007fb6f56967b0 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 0000000000062a19 R15: 00007ffd8e3b5a70 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:6/1095: #0: ffff88801e6cc948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffffc9000442fd18 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214 #2: ffff88807d41cb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x1b3/0x820 mm/page-writeback.c:2687 2 locks held by getty/5594: #0: ffff888034c7a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/5824: #0: ffff88802f5ac580 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline] #0: ffff88802f5ac580 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6366 #1: ffff88807d41a518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x177/0x380 mm/memory.c:3256 #2: ffff88807d41e950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xf6c/0x1430 fs/jbd2/transaction.c:448 3 locks held by syz.3.5193/17681: #0: ffff88803206dd18 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline] #0: ffff88803206dd18 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6366 #1: ffff88807d41a518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x177/0x380 mm/memory.c:3256 #2: ffff88807d41e950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xf6c/0x1430 fs/jbd2/transaction.c:448 2 locks held by syz.3.5193/17684: #0: ffff88807d41a0e0 (&type->s_umount_key#31){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807d41a0e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_lock+0x31a/0x3f0 fs/super.c:120 #1: ffff8880288c67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880288c67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19d/0xa50 fs/fs-writeback.c:2819 3 locks held by syz.1.5199/17696: #0: ffff88807b0baec8 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline] #0: ffff88807b0baec8 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6366 #1: ffff88807d41a518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x177/0x380 mm/memory.c:3256 #2: ffff88807d41e950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xf6c/0x1430 fs/jbd2/transaction.c:448 3 locks held by syz.0.5200/17698: #0: ffff88805d74d730 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:717 [inline] #0: ffff88805d74d730 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6366 #1: ffff88807d41a518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x177/0x380 mm/memory.c:3256 #2: ffff88807d41e950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xf6c/0x1430 fs/jbd2/transaction.c:448 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0 Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244