INFO: task kworker/u4:11:3500 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:11 state:D stack:22960 pid:3500 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_mb_mark_diskspace_used+0x27c/0x14b0 fs/ext4/mballoc.c:4050 ext4_mb_new_blocks+0x105b/0x42f0 fs/ext4/mballoc.c:6272 ext4_ext_map_blocks+0x1811/0x68c0 fs/ext4/extents.c:4416 ext4_map_blocks+0x9db/0x1a90 fs/ext4/inode.c:654 mpage_map_one_extent fs/ext4/inode.c:2205 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2258 [inline] ext4_do_writepages+0x1463/0x3990 fs/ext4/inode.c:2733 ext4_writepages+0x1dd/0x350 fs/ext4/inode.c:2822 do_writepages+0x351/0x590 mm/page-writeback.c:2575 __writeback_single_inode+0x14e/0xee0 fs/fs-writeback.c:1701 writeback_sb_inodes+0x813/0x1020 fs/fs-writeback.c:1992 __writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2063 wb_writeback+0x472/0xbe0 fs/fs-writeback.c:2173 wb_check_old_data_flush fs/fs-writeback.c:2277 [inline] wb_do_writeback fs/fs-writeback.c:2330 [inline] wb_workfn+0xad7/0xe60 fs/fs-writeback.c:2358 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INFO: task jbd2/sda1-8:5105 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:26024 pid:5105 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_buffer include/linux/buffer_head.h:373 [inline] jbd2_journal_commit_transaction+0x2e8d/0x5ad0 fs/jbd2/commit.c:815 kjournald2+0x40f/0x810 fs/jbd2/journal.c:201 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INFO: task syz-executor:5764 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21320 pid:5764 ppid:5763 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x13f/0x720 fs/ext4/inode.c:6129 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2537 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6284 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xd4d/0x34d0 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7ff0b5e705e3 RSP: 002b:00007fffe0665c30 EFLAGS: 00010206 RAX: 00007ff0b2bfc17c RBX: 00007fffe0665d60 RCX: 0000000000000000 RDX: 00007ff0b2bfc178 RSI: 0000000000000008 RDI: 00007fffe0665d60 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fffe0665d40 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000003e84 R14: ffffffffffffc17c R15: 0000000000000000 INFO: task syz.1.22:5913 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.22 state:D stack:25384 pid:5913 ppid:5779 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x13f/0x720 fs/ext4/inode.c:6129 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2537 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6284 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 do_shared_fault mm/memory.c:4717 [inline] do_fault mm/memory.c:4779 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1a2c/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7efda8672ba9 RSP: 002b:00007ffcbff02430 EFLAGS: 00010202 RAX: 0000001b2df24000 RBX: ffffffff86bd3aee RCX: 0000001b2df23ff8 RDX: 00000000005ffde8 RSI: 00000000005ffde8 RDI: 00007efda9555700 RBP: 0000000000000001 R08: 0000000000000000 R09: 00007efda8a12000 R10: 00007efda9555700 R11: 0000000000000000 R12: 00007efda8a26038 R13: 0000000000006e81 R14: ffffffff86bd3b2c R15: 00007efda9555720 INFO: task syz.3.30:5934 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.30 state:D stack:27560 pid:5934 ppid:5777 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x13f/0x720 fs/ext4/inode.c:6129 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2537 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6284 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 do_shared_fault mm/memory.c:4717 [inline] do_fault mm/memory.c:4779 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1a2c/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f1d9346bea3 RSP: 002b:00007fff89fef2a0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b2db64000 RDX: 0000001b2db24000 RSI: 0000000000600000 RDI: 00007f1d937e3708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff89fef530 INFO: task syz.2.31:5935 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.31 state:D stack:27560 pid:5935 ppid:5778 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 io_schedule+0x80/0xd0 kernel/sched/core.c:9024 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9f/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x13c/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x5c9/0xe00 fs/jbd2/transaction.c:1096 jbd2_journal_get_write_access+0x10c/0x140 fs/jbd2/transaction.c:1231 __ext4_journal_get_write_access+0x208/0x6d0 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x205/0x2a0 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x13f/0x720 fs/ext4/inode.c:6129 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6166 __mark_inode_dirty+0x2cc/0xc90 fs/fs-writeback.c:2537 generic_update_time fs/inode.c:1981 [inline] inode_update_time fs/inode.c:1994 [inline] __file_update_time fs/inode.c:2180 [inline] file_update_time+0x187/0x1a0 fs/inode.c:2210 ext4_page_mkwrite+0x1f9/0x11a0 fs/ext4/inode.c:6284 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 do_shared_fault mm/memory.c:4717 [inline] do_fault mm/memory.c:4779 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1a2c/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f6cc986bea3 RSP: 002b:00007ffe64c5f2b0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b2da64000 RDX: 0000001b2da24000 RSI: 0000000000600000 RDI: 00007f6cc9be3708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe64c5f540 Showing all locks held in the system: 3 locks held by kworker/0:0/8: #0: ffff8880b8c3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559 #1: ffff8880b8c28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #1: ffff8880b8c28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6696 #2: ffffffff8df37b48 (rcu_state.exp_wake_mutex){+.+.}-{3:3}, at: rcu_exp_wait_wake kernel/rcu/tree_exp.h:707 [inline] #2: ffffffff8df37b48 (rcu_state.exp_wake_mutex){+.+.}-{3:3}, at: rcu_exp_sel_wait_wake+0x18e0/0x1e40 kernel/rcu/tree_exp.h:736 1 lock held by khungtaskd/29: #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8df320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6669 3 locks held by kworker/u4:5/60: 5 locks held by kworker/u4:10/3491: 7 locks held by kworker/u4:11/3500: #0: ffff888141e52138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline] #0: ffff888141e52138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734 #1: ffffc9000cfc7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline] #1: ffffc9000cfc7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734 #2: ffff88802dc340e0 (&type->s_umount_key#31){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 #3: ffff88802dc36c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1768 [inline] #3: ffff88802dc36c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2821 #4: ffff88814dd08990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 #5: ffff888076536688 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x918/0x1a90 fs/ext4/inode.c:647 #6: ffffe8ffffc1fbd8 (&lg->lg_mutex){+.+.}-{3:3}, at: ext4_mb_group_or_file fs/ext4/mballoc.c:5822 [inline] #6: ffffe8ffffc1fbd8 (&lg->lg_mutex){+.+.}-{3:3}, at: ext4_mb_initialize_context+0x8af/0xc80 fs/ext4/mballoc.c:5866 2 locks held by getty/5539: #0: ffff88802e8bb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 3 locks held by syz-executor/5764: #0: ffff8880300ac420 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff8880300ac420 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff8880300ac420 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6283 #2: ffff88814dd08990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 3 locks held by syz.1.22/5913: #0: ffff8880326501a0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff8880326501a0 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff8880326501a0 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6283 #2: ffff88814dd08990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 3 locks held by syz.3.30/5934: #0: ffff88807ad36a20 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807ad36a20 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807ad36a20 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6283 #2: ffff88814dd08990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 3 locks held by syz.2.31/5935: #0: ffff88807ad35720 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807ad35720 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807ad35720 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88802dc34510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6283 #2: ffff88814dd08990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1f3f/0x2170 fs/jbd2/transaction.c:448 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf59/0xfa0 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5131 Comm: klogd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:qlink_to_object mm/kasan/quarantine.c:138 [inline] RIP: 0010:qlink_free mm/kasan/quarantine.c:143 [inline] RIP: 0010:qlist_free_all+0x3f/0xd0 mm/kasan/quarantine.c:185 Code: 00 49 89 f6 48 89 fb 49 bd 00 00 00 00 00 fc ff df 49 89 ef 4d 89 f4 4d 85 f6 75 0b 4c 89 ff e8 c7 04 00 00 49 89 c4 49 8b 2f <49> 63 84 24 c0 00 00 00 49 29 c7 4c 89 e7 4c 89 fe e8 cb e8 ff ff RSP: 0018:ffffc9001068f738 EFLAGS: 00000282 RAX: ffff888141a6b640 RBX: ffffc9001068f770 RCX: ffffea0000b20640 RDX: ffffea0000000000 RSI: ffffffff8acacfe0 RDI: ffff88802c819c80 RBP: ffff888051de2000 R08: ffffffff91ff152f R09: 1ffffffff23fe2a5 R10: dffffc0000000000 R11: fffffbfff23fe2a6 R12: ffff888141a6b640 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88802c819c80 FS: 00007f5269401c80(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ed18413168 CR3: 0000000031812000 CR4: 00000000003506f0 Call Trace: kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x1af/0x310 mm/slub.c:3540 __alloc_skb+0x103/0x2c0 net/core/skbuff.c:643 alloc_skb include/linux/skbuff.h:1316 [inline] alloc_skb_with_frags+0xcd/0x7a0 net/core/skbuff.c:6365 sock_alloc_send_pskb+0x883/0x9a0 net/core/sock.c:2829 unix_dgram_sendmsg+0x5a9/0x16e0 net/unix/af_unix.c:2013 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5269551407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe354985c0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f5269401c80 RCX: 00007f5269551407 RDX: 0000000000000049 RSI: 00007ffe35498700 RDI: 0000000000000003 RBP: 00007ffe35498b30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffe35498b48 R13: 00007ffe35498700 R14: 000000000000002e R15: 00007ffe35498700