INFO: task syz-executor.1:15051 blocked for more than 143 seconds. Not tainted 5.15.127-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:21120 pid:15051 ppid: 1 flags:0x00004006 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 rwsem_down_write_slowpath+0xebb/0x15c0 kernel/locking/rwsem.c:1157 __down_write_common kernel/locking/rwsem.c:1284 [inline] __down_write kernel/locking/rwsem.c:1293 [inline] down_write+0x164/0x170 kernel/locking/rwsem.c:1542 inode_lock include/linux/fs.h:787 [inline] vfs_unlink+0xe0/0x5f0 fs/namei.c:4198 do_unlinkat+0x49d/0x940 fs/namei.c:4277 __do_sys_unlink fs/namei.c:4325 [inline] __se_sys_unlink fs/namei.c:4323 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4323 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f7cc6632297 RSP: 002b:00007ffc5d785db8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7cc6632297 RDX: 00007ffc5d785de0 RSI: 00007ffc5d785e70 RDI: 00007ffc5d785e70 RBP: 00007ffc5d785e70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc5d786f30 R13: 00007f7cc667d3b9 R14: 000000000026ae5d R15: 0000000000000008 INFO: task syz-executor.1:15235 blocked for more than 143 seconds. Not tainted 5.15.127-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:21984 pid:15235 ppid: 15051 flags:0x00004002 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:2662 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2710 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 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:867 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: 0033:0xc8 RSP: 002b:0000000020000118 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f7cc6751f80 RCX: 00007f7cc6632ae9 RDX: 0000000020000040 RSI: 0000000020000110 RDI: 0000000000002000 RBP: 00007f7cc667e47a R08: 0000000020000240 R09: 0000000020000240 R10: 0000000020000200 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7cc6751f80 R15: 00007ffc5d786b98 INFO: task syz-executor.1:15695 blocked for more than 144 seconds. Not tainted 5.15.127-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:22304 pid:15695 ppid: 15051 flags:0x00004002 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:2662 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2710 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 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:867 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: 0033:0xc8 RSP: 002b:0000000020000118 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f7cc6751f80 RCX: 00007f7cc6632ae9 RDX: 00000000200001c0 RSI: 0000000020000110 RDI: 0000000000002000 RBP: 00007f7cc667e47a R08: 0000000020000240 R09: 0000000020000240 R10: 0000000020000200 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7cc6751f80 R15: 00007ffc5d786b98 INFO: task syz-executor.1:15793 blocked for more than 145 seconds. Not tainted 5.15.127-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:23392 pid:15793 ppid: 15051 flags:0x00004002 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:2662 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2710 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 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:867 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: 0033:0xc8 RSP: 002b:0000000020000118 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f7cc6751f80 RCX: 00007f7cc6632ae9 RDX: 00000000200001c0 RSI: 0000000020000110 RDI: 0000000000002000 RBP: 00007f7cc667e47a R08: 0000000020000240 R09: 0000000020000240 R10: 0000000020000200 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7cc6751f80 R15: 00007ffc5d786b98 INFO: task syz-executor.1:15879 blocked for more than 146 seconds. Not tainted 5.15.127-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:22784 pid:15879 ppid: 15051 flags:0x00004002 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:2662 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2710 ext4_nonda_switch fs/ext4/inode.c:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 elf_core_dump+0x2b1c/0x4570 fs/binfmt_elf.c:2264 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:867 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: 0033:0xc8 RSP: 002b:0000000020000118 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f7cc6751f80 RCX: 00007f7cc6632ae9 RDX: 00000000200001c0 RSI: 0000000020000110 RDI: 0000000000002000 RBP: 00007f7cc667e47a R08: 0000000020000240 R09: 0000000020000240 R10: 0000000020000200 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7cc6751f80 R15: 00007ffc5d786b98 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: 1 lock held by khungtaskd/27: #0: ffffffff8c91f0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3245: #0: ffff88814b9c8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 3 locks held by kworker/u4:2/6402: #0: ffff8880b9b39718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9b27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891 #2: ffffffff8c91f0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:7/16235: 4 locks held by kworker/u4:8/31311: #0: ffff8880b9a39718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9a27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891 #2: ffffffff8c91f0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 #3: ffffffff8c91f0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by syz-executor.1/15051: #0: ffff88814b9e6460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377 #1: ffff88805947b5c8 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff88805947b5c8 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_unlinkat+0x260/0x940 fs/namei.c:4260 #2: ffff888056dd53b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #2: ffff888056dd53b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4198 3 locks held by syz-executor.1/15235: #0: ffff88814b9e6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880317797e0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880317797e0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b9e60e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2707 2 locks held by syz-executor.4/15683: 3 locks held by syz-executor.1/15695: #0: ffff88814b9e6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880596949b8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880596949b8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b9e60e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2707 1 lock held by syz-executor.4/15716: 2 locks held by syz-executor.4/15778: 3 locks held by syz-executor.1/15793: #0: ffff88814b9e6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880260883f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff8880260883f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b9e60e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2707 1 lock held by syz-executor.4/15811: 3 locks held by syz-executor.1/15879: #0: ffff88814b9e6460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff888056dd53b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff888056dd53b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff88814b9e60e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2707 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.127-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 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: 9 Comm: kworker/u4:0 Not tainted 5.15.127-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: writeback wb_workfn (flush-8:0) RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline] RIP: 0010:write_comp_data kernel/kcov.c:218 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x30/0x80 kernel/kcov.c:270 Code: 8b 15 74 59 82 7e 65 8b 05 75 59 82 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83 ba 34 16 00 00 00 74 52 8b 82 10 16 00 00 <83> f8 03 75 47 48 8b 8a 18 16 00 00 44 8b 92 14 16 00 00 49 c1 e2 RSP: 0018:ffffc90000ce69d8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff83eb0203 RDX: ffff88813fe90000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc90000ce6b10 R08: ffffffff83eb0222 R09: fffffbfff1bc80ee R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff888053d53280 R14: ffff888053d53201 R15: 1ffff1100a7aa65a FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00093a000 CR3: 0000000019335000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: variable_test_bit arch/x86/include/asm/bitops.h:214 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:135 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_block_bio_queue include/trace/events/block.h:332 [inline] submit_bio_checks+0xe12/0x1920 block/blk-core.c:893 __submit_bio+0x5a1/0x850 block/blk-core.c:917 __submit_bio_noacct_mq block/blk-core.c:1003 [inline] submit_bio_noacct+0x955/0xb30 block/blk-core.c:1033 submit_bio+0x2dd/0x560 block/blk-core.c:1095 ext4_io_submit+0x155/0x200 fs/ext4/page-io.c:381 ext4_writepages+0x2c73/0x3d10 fs/ext4/inode.c:2837 do_writepages+0x481/0x730 mm/page-writeback.c:2364 __writeback_single_inode+0x15b/0xe30 fs/fs-writeback.c:1625 writeback_sb_inodes+0xbf0/0x1a50 fs/fs-writeback.c:1908 wb_writeback+0x451/0xc50 fs/fs-writeback.c:2082 wb_do_writeback fs/fs-writeback.c:2225 [inline] wb_workfn+0x46c/0x1130 fs/fs-writeback.c:2266 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298