INFO: task syz-executor.3:4953 blocked for more than 143 seconds. Not tainted 5.15.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:22840 pid: 4953 ppid: 3549 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2659 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2707 ext4_nonda_switch fs/ext4/inode.c:2943 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2970 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 ext4_buffered_write_iter+0x22e/0x380 fs/ext4/file.c:269 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 dump_user_range+0x91/0x320 fs/coredump.c:949 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:314 exc_page_fault+0x342/0x740 arch/x86/mm/fault.c:1544 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x6ba5ac1c52 RSP: 002b:0000000020000338 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007fa1522df120 RCX: 00007fa1521bf169 RDX: 0000000000000000 RSI: 0000000020000330 RDI: 0000000000008000 RBP: 00007fa15221aca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe85aa104f R14: 00007fa1514ef300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8c91c4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:2/154: #0: ffff888011c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc9000126fd20 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 2 locks held by getty/3262: #0: ffff88814b1ba098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900020a32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147 3 locks held by kworker/u4:7/4246: #0: ffff888013db5138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc9000381fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 3 locks held by syz-executor.3/4953: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880720d67a0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880720d67a0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb9/0x380 fs/ext4/file.c:263 #2: ffff88814b2f60e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2704 3 locks held by syz-executor.1/5867: 1 lock held by syz-executor.3/5885: 1 lock held by syz-executor.3/6567: 2 locks held by syz-executor.2/6783: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 #1: ffff8880b9a39698 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 3 locks held by syz-executor.1/6795: 2 locks held by syz-executor.3/6807: 1 lock held by syz-executor.2/6894: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 1 lock held by syz-executor.0/7050: 1 lock held by syz-executor.2/7062: 1 lock held by syz-executor.1/8054: 1 lock held by syz-executor.2/8064: 3 locks held by syz-executor.3/8070: 1 lock held by syz-executor.4/8094: 1 lock held by syz-executor.1/8099: 1 lock held by syz-executor.1/8100: 1 lock held by syz-executor.1/8101: 1 lock held by syz-executor.4/8131: 1 lock held by syz-executor.5/8133: 1 lock held by syz-executor.0/8134: 1 lock held by syz-executor.0/8142: 1 lock held by syz-executor.2/8157: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 1 lock held by syz-executor.1/8160: 1 lock held by syz-executor.3/8165: 1 lock held by syz-executor.4/8166: 1 lock held by syz-executor.2/8170: 1 lock held by syz-executor.5/8199: 1 lock held by syz-executor.5/8203: 1 lock held by syz-executor.1/8205: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 1 lock held by syz-executor.0/8212: 1 lock held by syz-executor.3/8216: 1 lock held by syz-executor.2/8218: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 1 lock held by syz-executor.0/8222: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 1 lock held by syz-executor.2/8229: 1 lock held by syz-executor.3/8230: 1 lock held by syz-executor.2/8232: 1 lock held by syz-executor.0/8263: 1 lock held by syz-executor.3/8267: 2 locks held by syz-executor.4/8290: 1 lock held by syz-executor.1/8294: 1 lock held by syz-executor.4/8296: 1 lock held by syz-executor.2/8305: 1 lock held by syz-executor.5/8313: 2 locks held by syz-executor.4/8330: 2 locks held by syz-executor.4/8339: 1 lock held by syz-executor.4/8340: 1 lock held by syz-executor.2/8350: 1 lock held by syz-executor.1/8352: 1 lock held by syz-executor.3/8405: 1 lock held by syz-executor.2/8518: 1 lock held by syz-executor.0/8600: 1 lock held by syz-executor.5/8621: 1 lock held by syz-executor.2/8627: 2 locks held by syz-executor.0/8852: 1 lock held by syz-executor.1/8988: 1 lock held by syz-executor.5/8992: 1 lock held by syz-executor.2/9265: 1 lock held by syz-executor.1/9665: 1 lock held by syz-executor.3/9909: 1 lock held by syz-executor.1/10004: #0: ffff88814b2f8bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2687 2 locks held by syz-executor.4/11718: 2 locks held by syz-executor.4/11720: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff88806a9a3fc0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88806a9a3fc0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb9/0x380 fs/ext4/file.c:263 2 locks held by syz-executor.4/11721: 1 lock held by syz-executor.5/11740: 2 locks held by syz-executor.5/11741: 2 locks held by syz-executor.3/11743: 2 locks held by syz-executor.1/11746: 2 locks held by syz-executor.5/11751: 3 locks held by syz-executor.0/11759: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880720e35c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880720e35c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb9/0x380 fs/ext4/file.c:263 #2: ffff88814b2fa3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_log_do_checkpoint+0xd61/0x1660 fs/jbd2/checkpoint.c:284 3 locks held by syz-executor.3/11760: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff88806d1997e0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88806d1997e0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb9/0x380 fs/ext4/file.c:263 #2: ffff8880b9b39698 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 3 locks held by syz-executor.3/11761: 2 locks held by syz-executor.1/11763: 3 locks held by syz-executor.0/11764: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff88806d19abd0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88806d19abd0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb9/0x380 fs/ext4/file.c:263 #2: ffff88814b2fa990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x12d5/0x1590 fs/jbd2/transaction.c:466 3 locks held by syz-executor.2/11765: 2 locks held by syz-executor.1/11768: 2 locks held by syz-executor.4/11769: 2 locks held by syz-executor.4/11773: 2 locks held by syz-executor.2/11775: 3 locks held by syz-executor.4/11778: 2 locks held by syz-executor.0/11786: 2 locks held by syz-executor.0/11797: 2 locks held by syz-executor.0/11798: 3 locks held by syz-executor.1/11801: 2 locks held by syz-executor.5/11806: 2 locks held by syz-executor.2/11812: 2 locks held by syz-executor.5/11817: 2 locks held by syz-executor.1/11823: 2 locks held by syz-executor.5/11824: 2 locks held by syz-executor.4/11825: 2 locks held by syz-executor.2/11829: 3 locks held by syz-executor.3/11833: 2 locks held by syz-executor.2/11831: 3 locks held by syz-executor.1/11835: 1 lock held by syz-executor.3/11837: #0: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #0: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:840 1 lock held by syz-executor.4/11840: #0: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:840 2 locks held by syz-executor.0/11855: 1 lock held by syz-executor.2/11859: 3 locks held by syz-executor.5/11864: 2 locks held by syz-executor.0/11870: 2 locks held by syz-executor.2/11871: 2 locks held by syz-executor.2/11876: 2 locks held by syz-executor.3/11879: 2 locks held by syz-executor.3/11881: 2 locks held by syz-executor.4/11888: 3 locks held by syz-executor.3/11894: 2 locks held by syz-executor.4/11895: 2 locks held by syz-executor.4/11896: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377 #1: ffff8880722d7198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880722d7198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: open_last_lookups fs/namei.c:3459 [inline] #1: ffff8880722d7198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: path_openat+0x824/0x2f20 fs/namei.c:3669 2 locks held by syz-executor.1/11898: 2 locks held by syz-executor.5/11899: 3 locks held by syz-executor.1/11902: 2 locks held by syz-executor.5/11912: 2 locks held by syz-executor.0/11927: 2 locks held by syz-executor.2/11928: 3 locks held by syz-executor.0/11938: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377 #1: ffff88806abf83f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff88806abf83f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_unlinkat+0x260/0x940 fs/namei.c:4260 #2: ffff88806d090de8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #2: ffff88806d090de8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4198 2 locks held by syz-executor.0/11939: #0: ffff88814b2f6460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377 #1: ffff88806abf83f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff88806abf83f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_unlinkat+0x260/0x940 fs/namei.c:4260 2 locks held by syz-executor.3/11941: 1 lock held by syz-executor.2/11942: 2 locks held by syz-executor.3/11943: 2 locks held by syz-executor.3/11944: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.15.109-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1219 Comm: kworker/u4:5 Not tainted 5.15.109-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:725 [inline] RIP: 0010:__unlock_page_memcg+0xb5/0x110 mm/memcontrol.c:2090 Code: 2f 00 74 08 4c 89 e7 e8 99 3f fb ff 48 c7 83 b0 06 00 00 00 00 00 00 48 81 c3 70 06 00 00 48 89 df 48 8b 34 24 e8 3b 86 55 08 76 34 4c 08 85 c0 74 3a e8 6d c6 9c ff 84 c0 75 31 e8 64 34 4c RSP: 0018:ffffc900059df8c0 EFLAGS: 00000207 RAX: ffff88801d57d700 RBX: ffff888073d9c000 RCX: ffffffff81cea338 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888073d9c000 RBP: 1ffff1100e7b3a11 R08: dffffc0000000000 R09: fffff94000acfb09 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888073d9d088 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffea19adfe8 CR3: 000000006e14f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: test_clear_page_writeback+0xb29/0xd30 mm/page-writeback.c:2813 end_page_writeback+0x2a6/0x690 mm/filemap.c:1603 ext4_finish_bio+0x751/0x8b0 fs/ext4/page-io.c:145 ext4_release_io_end+0xdf/0x2c0 fs/ext4/page-io.c:160 ext4_end_io_end fs/ext4/page-io.c:194 [inline] ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline] ext4_end_io_rsv_work+0x5d6/0x6e0 fs/ext4/page-io.c:273 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298