INFO: task syz-executor:5814 blocked for more than 143 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23240 pid:5814 tgid:5814 ppid:5812 task_flags:0x440100 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 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+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x93d/0x12a0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x320 fs/ext4/inode.c:5892 __ext4_mark_inode_dirty+0x197/0x870 fs/ext4/inode.c:6066 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6103 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 wp_page_shared mm/memory.c:3688 [inline] do_wp_page+0xb9e/0x58e0 mm/memory.c:3907 handle_pte_fault mm/memory.c:6013 [inline] __handle_mm_fault+0x1ada/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 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: 0033:0x7f4a33677dcf RSP: 002b:00007ffd329952c0 EFLAGS: 00010246 RAX: 00007f4a31ce0000 RBX: 00005555907c3fd0 RCX: 0000000000000000 RDX: 1ffffffff156f9d8 RSI: 00005555907c0550 RDI: 0000000000000001 RBP: 00007ffd329955b0 R08: 00005555907c05c8 R09: 0000000000001f3b R10: 0000000000000001 R11: 00007ffd329957c0 R12: 00007ffd32995610 R13: 0000000000000004 R14: 00007ffd32995330 R15: 00007ffd32995400 INFO: task syz.6.8362:26755 blocked for more than 144 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.8362 state:D stack:27416 pid:26755 tgid:26755 ppid:25402 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 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+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x93d/0x12a0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x320 fs/ext4/inode.c:5892 __ext4_mark_inode_dirty+0x197/0x870 fs/ext4/inode.c:6066 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6103 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 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: 0033:0x7ff15b86f282 RSP: 002b:00007fff45858d60 EFLAGS: 00010202 RAX: 000000000000e008 RBX: 00007ff15c6e5720 RCX: 0000000000000000 RDX: 0000001b2d712000 RSI: 0000000000000008 RDI: 00007ff15c6e5720 RBP: 0000000000000695 R08: 00007ff15afff058 R09: 00007ff15bba2000 R10: 00007ff15afff008 R11: 0000000000000002 R12: ffffffff84814304 R13: 00007ff15bbb6038 R14: 0000000000000168 R15: ffffffffffff2000 INFO: task syz.5.8363:26757 blocked for more than 144 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.8363 state:D stack:28344 pid:26757 tgid:26757 ppid:24551 task_flags:0x440040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 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+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x93d/0x12a0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x320 fs/ext4/inode.c:5892 __ext4_mark_inode_dirty+0x197/0x870 fs/ext4/inode.c:6066 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6103 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 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: 0033:0x7f93f066f282 RSP: 002b:00007fff12ff65d0 EFLAGS: 00010202 RAX: 0000000000008008 RBX: 00007f93f14e5720 RCX: 0000000000000000 RDX: 0000001b30918000 RSI: 0000000000000008 RDI: 00007f93f14e5720 RBP: 0000000000000a33 R08: 00007f93efdff078 R09: 00007f93f09a2000 R10: 00007f93efdff008 R11: 0000000000000001 R12: ffffffff8984ad2f R13: 00007f93f09b6038 R14: 00000000000001be R15: ffffffffffff8000 INFO: task syz.3.8364:26760 blocked for more than 144 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.8364 state:D stack:28632 pid:26760 tgid:26760 ppid:5827 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 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+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x93d/0x12a0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x320 fs/ext4/inode.c:5892 __ext4_mark_inode_dirty+0x197/0x870 fs/ext4/inode.c:6066 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6103 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 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: 0033:0x7fd71006547b RSP: 002b:00007fffa31f0cc0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b2fc20000 RSI: 0000000000600000 RDI: 00007fd710298d50 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 00000000000a6f32 R15: 00007fffa31f0f70 INFO: task syz.0.8365:26761 blocked for more than 145 seconds. Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.8365 state:D stack:28632 pid:26761 tgid:26761 ppid:22928 task_flags:0x440040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 io_schedule+0xbf/0x130 kernel/sched/core.c:7742 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+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:105 [inline] do_get_write_access+0x93d/0x12a0 fs/jbd2/transaction.c:1092 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1be/0x320 fs/ext4/inode.c:5892 __ext4_mark_inode_dirty+0x197/0x870 fs/ext4/inode.c:6066 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6103 __mark_inode_dirty+0x1eb/0xe50 fs/fs-writeback.c:2527 generic_update_time+0xcf/0xf0 fs/inode.c:2064 inode_update_time fs/inode.c:2077 [inline] __file_update_time fs/inode.c:2305 [inline] file_update_time+0x17d/0x1c0 fs/inode.c:2335 ext4_page_mkwrite+0x35e/0x1750 fs/ext4/inode.c:6221 do_page_mkwrite+0x171/0x380 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing+0x29c/0x3fb0 mm/memory.c:4160 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 do_user_addr_fault+0x60c/0x1370 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: 0033:0x7fabd866547b RSP: 002b:00007fffb2537c50 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b31720000 RSI: 0000000000600000 RDI: 00007fabd8898d50 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000927c0 R14: 00000000000a6f4e R15: 00007fffb2537f00 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 3 locks held by syz-executor/5814: #0: ffff8880732b8588 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff88814cfbe518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 #2: ffff88814de12950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 2 locks held by getty/22447: #0: ffff8880361290a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90003a972f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by syz.6.8362/26755: #0: ffff888032f5e448 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff88814cfbe518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 #2: ffff88814de12950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 3 locks held by syz.5.8363/26757: #0: ffff888053fdd6c8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff88814cfbe518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 #2: ffff88814de12950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 3 locks held by syz.3.8364/26760: #0: ffff888063087808 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff88814cfbe518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 #2: ffff88814de12950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 3 locks held by syz.0.8365/26761: #0: ffff8880631801c8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x452/0x1370 arch/x86/mm/fault.c:1328 #1: ffff88814cfbe518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x171/0x380 mm/memory.c:3287 #2: ffff88814de12950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U I 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 PREEMPT(full) Tainted: [U]=USER, [I]=FIRMWARE_WORKAROUND Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245