INFO: task kworker/u4:1:11 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:22112 pid:11 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit_lock+0xbe/0x560 kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0x138/0x190 kernel/sched/wait_bit.c:117 lock_buffer include/linux/buffer_head.h:397 [inline] do_get_write_access+0x1bc/0xf20 fs/jbd2/transaction.c:991 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_mb_mark_diskspace_used+0x1bf/0x1500 fs/ext4/mballoc.c:3838 ext4_mb_new_blocks+0x1170/0x44d0 fs/ext4/mballoc.c:5796 ext4_ext_map_blocks+0x18d1/0x6640 fs/ext4/extents.c:4361 ext4_map_blocks+0x9d7/0x1a90 fs/ext4/inode.c:681 mpage_map_one_extent fs/ext4/inode.c:2436 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2489 [inline] ext4_writepages+0x12aa/0x2e70 fs/ext4/inode.c:2857 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491 __writeback_single_inode+0x153/0x1170 fs/fs-writeback.c:1673 writeback_sb_inodes+0xad5/0x17f0 fs/fs-writeback.c:1964 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2035 wb_writeback+0x484/0xd40 fs/fs-writeback.c:2140 wb_check_old_data_flush fs/fs-writeback.c:2240 [inline] wb_do_writeback fs/fs-writeback.c:2293 [inline] wb_workfn+0xb68/0xee0 fs/fs-writeback.c:2321 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task jbd2/sda1-8:3602 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:25584 pid:3602 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_buffer include/linux/buffer_head.h:385 [inline] jbd2_journal_commit_transaction+0x2f0f/0x5f30 fs/jbd2/commit.c:849 kjournald2+0x40b/0x800 fs/jbd2/journal.c:210 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz-executor:4264 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:22256 pid:4264 ppid:4263 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 wp_page_shared+0x167/0x370 mm/memory.c:3358 handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x1b1b/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f5a9b670163 RSP: 002b:00007ffe03a08b00 EFLAGS: 00010202 RAX: 00007f5a941efb5c RBX: 00007ffe03a08c30 RCX: 0000000000000000 RDX: 00007f5a941efb58 RSI: 0000000000000008 RDI: 00007ffe03a08c30 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffe03a08c10 R11: 0000000000000000 R12: 0000000000000000 R13: 00000000000104a4 R14: fffffffffffefb5c R15: 0000000000000000 INFO: task syz.3.44:4485 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.44 state:D stack:26288 pid:4485 ppid:4279 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7ff08ec72729 RSP: 002b:00007ffd2a030d80 EFLAGS: 00010202 RAX: 0000001b30513000 RBX: ffffffff81ef612d RCX: 0000001b30512ff8 RDX: 0000001b2ff24220 RSI: 0000000000000008 RDI: 00007ff08fb55720 RBP: 000000000000016c R08: 00007ff08f010000 R09: 00007ff08f012000 R10: 0000000081ef6131 R11: 0000000000000004 R12: 00007ff08f026038 R13: 0000000000001ad6 R14: ffffffff81ef635a R15: 00007ff08fb55720 INFO: task syz.1.49:4502 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.49 state:D stack:26288 pid:4502 ppid:4277 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f608c672729 RSP: 002b:00007fff1a495610 EFLAGS: 00010202 RAX: 0000001b30321000 RBX: ffffffff81e38d20 RCX: 0000001b30320ff8 RDX: 0000001b2fd2421c RSI: 0000000000000008 RDI: 00007f608d555720 RBP: 00000000000000dc R08: 00007f608ca10000 R09: 00007f608ca12000 R10: 0000000081e38d24 R11: 0000000000000005 R12: 00007f608ca26038 R13: 00000000000005c6 R14: ffffffff81e381cc R15: 00007f608d555720 INFO: task syz.2.52:4514 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.52 state:D stack:27504 pid:4514 ppid:4286 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f3470a6ba23 RSP: 002b:00007ffc7ace0de0 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b2fe64000 RDX: 0000001b2fe24000 RSI: 0000000000400000 RDI: 00007f3470de0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc7ace1070 INFO: task syz.4.53:4515 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.53 state:D stack:27632 pid:4515 ppid:4278 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7ff8ac26ba23 RSP: 002b:00007fff28b19fc0 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b30064000 RDX: 0000001b30024000 RSI: 0000000000400000 RDI: 00007ff8ac5e0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff28b1a250 INFO: task syz.0.55:4518 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.55 state:D stack:27632 pid:4518 ppid:4281 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 do_shared_fault mm/memory.c:4694 [inline] do_fault mm/memory.c:4762 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f8cc906ba23 RSP: 002b:00007ffef2d77b90 EFLAGS: 00010246 RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b2fc64000 RDX: 0000001b2fc24000 RSI: 0000000000400000 RDI: 00007f8cc93e0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffef2d77e20 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: #0: ffff8880b8f3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 #1: ffff8880b8f27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x400/0x740 kernel/sched/psi.c:999 #2: ffff8880b8f28458 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999 6 locks held by kworker/u4:1/11: #0: ffff888019af9138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc90000107d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #2: ffff88814dda60e0 (&type->s_umount_key#31){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415 #3: ffff88814ddb0c18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717 #4: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 #5: ffff88807416aaa8 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x914/0x1a90 fs/ext4/inode.c:674 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527 2 locks held by getty/4033: #0: ffff88814d5c4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198 3 locks held by syz-executor/4264: #0: ffff88807a9bdb58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807a9bdb58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88807a9bdb58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 2 locks held by kworker/u4:7/4356: 3 locks held by syz.3.44/4485: #0: ffff88807b4f9058 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807b4f9058 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88807b4f9058 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 3 locks held by syz.1.49/4502: #0: ffff88802a040158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88802a040158 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88802a040158 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 3 locks held by syz.2.52/4514: #0: ffff88807b4f8158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807b4f8158 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88807b4f8158 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 3 locks held by syz.4.53/4515: #0: ffff88807b4fd3d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807b4fd3d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88807b4fd3d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 3 locks held by syz.0.55/4518: #0: ffff88802a0462d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88802a0462d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline] #0: ffff88802a0462d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382 #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline] #1: ffff88814dda6558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273 #2: ffff88814ddb2990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 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+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf0e/0xf50 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9 Comm: kworker/u4:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:820 [inline] RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] RIP: 0010:batadv_nc_worker+0x20c/0x600 net/batman-adv/network-coding.c:719 Code: c4 88 f7 e8 76 b4 36 00 89 c3 31 ff 89 c6 e8 cb c7 88 f7 85 db 74 15 e8 a2 be 72 f7 84 c0 74 18 e8 59 c4 88 f7 48 8b 5c 24 08 65 e8 4d c4 88 f7 48 8b 5c 24 08 eb 59 e8 41 b4 36 00 89 c3 31 RSP: 0018:ffffc900000e7be0 EFLAGS: 00000293 RAX: ffffffff89f969c7 RBX: ffff888057dd50c0 RCX: ffff88813fe70000 RDX: 0000000000000000 RSI: ffffffff8adf5dc0 RDI: ffffffff8adf5d80 RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff2162048 R10: dffffc0000000000 R11: fffffbfff2162049 R12: dffffc0000000000 R13: ffffffff89f9688e R14: ffff8880240acc80 R15: 000000000000002d FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055cc4e20f168 CR3: 000000000c88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295