INFO: task syz.5.142:7031 blocked for more than 143 seconds. Not tainted 6.12.0-rc6-syzkaller-00272-gda4373fbcf00 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.142 state:D stack:24704 pid:7031 tgid:7015 ppid:5954 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 exfat_get_block+0x1c3/0x2180 fs/exfat/inode.c:278 get_more_blocks fs/direct-io.c:648 [inline] do_direct_IO fs/direct-io.c:936 [inline] __blockdev_direct_IO+0x1c8e/0x4890 fs/direct-io.c:1243 blockdev_direct_IO include/linux/fs.h:3280 [inline] exfat_direct_IO+0x151/0x400 fs/exfat/inode.c:482 generic_file_direct_write+0x17a/0x390 mm/filemap.c:3977 __generic_file_write_iter+0x126/0x230 mm/filemap.c:4141 exfat_file_write_iter+0x165/0x3f0 fs/exfat/file.c:598 do_iter_readv_writev+0x600/0x880 vfs_writev+0x376/0xba0 fs/read_write.c:1064 do_pwritev fs/read_write.c:1165 [inline] __do_sys_pwritev2 fs/read_write.c:1224 [inline] __se_sys_pwritev2+0x1ca/0x2d0 fs/read_write.c:1215 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e2a17e719 RSP: 002b:00007f5e285f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f5e2a336058 RCX: 00007f5e2a17e719 RDX: 0000000000000001 RSI: 00000000200001c0 RDI: 0000000000000004 RBP: 00007f5e2a1f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5e2a336058 R15: 00007ffef5944d68 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 4 locks held by kworker/u8:2/35: #0: ffff888143a9e148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888143a9e148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000ab7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000ab7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff8880120920e0 (&type->s_umount_key#51){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff8880120900e8 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 3 locks held by kworker/1:1/46: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000b67d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000b67d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc1448 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 5 locks held by kworker/u8:3/53: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000be7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000be7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb4910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcc1448 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616 #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by kworker/u8:4/61: 2 locks held by kworker/u8:6/3421: 2 locks held by getty/5582: #0: ffff8880304c80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by syz.5.142/7016: 3 locks held by syz.5.142/7031: #0: ffff888012092420 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888012092420 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x2d1/0xba0 fs/read_write.c:1062 #1: ffff88805be095f0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805be095f0 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: exfat_file_write_iter+0x9e/0x3f0 fs/exfat/file.c:579 #2: ffff8880120900e8 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_get_block+0x1c3/0x2180 fs/exfat/inode.c:278 2 locks held by kworker/u8:10/7308: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90004487d00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004487d00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 2 locks held by syz-executor/8183: 2 locks held by syz.8.314/8667: 1 lock held by kworker/u8:10/8682: 1 lock held by syz.3.317/8690: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00272-gda4373fbcf00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7016 Comm: syz.5.142 Not tainted 6.12.0-rc6-syzkaller-00272-gda4373fbcf00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:65 Code: d1 fc ff e8 02 7d ff ff eb a8 e8 4b e0 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 89 fe 48 c7 c7 e0 35 60 8c e9 bd fe ff ff 66 2e 0f RSP: 0018:ffffc9000331f3b8 EFLAGS: 00000082 RAX: ffffffff821fe4c4 RBX: 00000000000000cc RCX: 0000000000040000 RDX: ffffc900168d8000 RSI: 000000000003ffff RDI: ffffffff8c198140 RBP: ffffc9000331f4f0 R08: ffffffff821fe51d R09: 1ffffffff347cd7c R10: dffffc0000000000 R11: fffffbfff347cd7d R12: ffff88805efae1d0 R13: 0000000000039958 R14: fffffffffffffffd R15: 00000000000000dc FS: 00007f5e2aea06c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdb5f588000 CR3: 0000000027480000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lookup_bh_lru fs/buffer.c:1371 [inline] __find_get_block+0x477/0x1150 fs/buffer.c:1400 bdev_getblk+0x33/0x550 fs/buffer.c:1431 __bread_gfp+0x86/0x400 fs/buffer.c:1491 sb_bread include/linux/buffer_head.h:346 [inline] exfat_get_dentry+0x53b/0x730 fs/exfat/dir.c:691 exfat_readdir fs/exfat/dir.c:121 [inline] exfat_iterate+0xb69/0x3390 fs/exfat/dir.c:261 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65 iterate_dir+0x571/0x800 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:407 [inline] __se_sys_getdents64+0x1d3/0x4a0 fs/readdir.c:392 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e2a17e719 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5e2aea0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f5e2a335f80 RCX: 00007f5e2a17e719 RDX: 0000000000001000 RSI: 0000000020000f80 RDI: 0000000000000006 RBP: 00007f5e2a1f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5e2a335f80 R15: 00007ffef5944d68