INFO: task syz.4.388:10114 blocked for more than 144 seconds. Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.388 state:D stack:27392 pid:10114 tgid:10112 ppid:8645 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 fdget_pos+0x24e/0x320 fs/file.c:1160 ksys_read+0x7e/0x2b0 fs/read_write.c:703 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: 0033:0x7f8f0617e719 RSP: 002b:00007f8f06ff2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f8f06336058 RCX: 00007f8f0617e719 RDX: 0000000000002020 RSI: 0000000020002a80 RDI: 0000000000000007 RBP: 00007f8f061f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f8f06336058 R15: 00007fff00ffa5c8 INFO: task syz.4.388:10115 blocked for more than 144 seconds. Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.388 state:D stack:23520 pid:10115 tgid:10112 ppid:8645 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 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:815 [inline] open_last_lookups fs/namei.c:3691 [inline] path_openat+0x89a/0x3590 fs/namei.c:3930 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1441 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: 0033:0x7f8f0617e719 RSP: 002b:00007f8f06fd1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8f06336130 RCX: 00007f8f0617e719 RDX: 000000000002a442 RSI: 00000000200001c0 RDI: ffffffffffffff9c RBP: 00007f8f061f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8f06336130 R15: 00007fff00ffa5c8 Showing all locks held in the system: 3 locks held by kworker/0:1/9: #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: ffffc900000e7d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900000e7d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 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/u8:3/53: #0: ffff888143ee1148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888143ee1148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000be7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000be7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff88805e8ea0e0 (&type->s_umount_key#83){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 #3: ffff88805e8ee0e8 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_write_inode+0xe5/0x1a0 fs/exfat/inode.c:108 3 locks held by kworker/u8:6/1141: 4 locks held by udevd/5203: #0: ffff888011cebd58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb4/0xd70 fs/seq_file.c:182 #1: ffff888026126488 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff88806f6343c8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff8880795e30e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8880795e30e8 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2736 1 lock held by dhcpcd/5497: #0: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1112 2 locks held by getty/5585: #0: ffff88814d06a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:9/6103: #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: ffffc9000538fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000538fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb48d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616 #4: ffffffff8e93d200 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4562 3 locks held by kworker/u8:10/6711: #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: ffffc90003e57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003e57d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by syz.4.388/10113: 1 lock held by syz.4.388/10114: #0: ffff8880537b49b8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24e/0x320 fs/file.c:1160 2 locks held by syz.4.388/10115: #0: ffff88805e8ea420 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88807910a2d0 (&sb->s_type->i_mutex_key#31){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88807910a2d0 (&sb->s_type->i_mutex_key#31){++++}-{3:3}, at: open_last_lookups fs/namei.c:3691 [inline] #1: ffff88807910a2d0 (&sb->s_type->i_mutex_key#31){++++}-{3:3}, at: path_openat+0x89a/0x3590 fs/namei.c:3930 7 locks held by syz-executor/11209: #0: ffff8880356f2420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff8880356f2420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:679 #1: ffff88807a0aa488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff888145310b48 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55f288 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 #4: ffff8880795e30e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8880795e30e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #5: ffff888052949250 (&devlink->lock_key#32){+.+.}-{3:3}, at: nsim_drv_probe+0xcb/0xb80 drivers/net/netdevsim/dev.c:1537 #6: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:678 [inline] #6: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: nsim_create+0x408/0x890 drivers/net/netdevsim/netdev.c:750 1 lock held by syz-executor/11451: #0: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc1408 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 2 locks held by syz.3.545/11480: #0: ffffffff8eec2f08 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree_super fs/btrfs/super.c:1843 [inline] #0: ffffffff8eec2f08 (uuid_mutex){+.+.}-{3:3}, at: btrfs_get_tree+0x2f4/0x1a10 fs/btrfs/super.c:2107 #1: ffffffff8e9f91e8 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:843 8 locks held by syz.9.547/11513: 2 locks held by syz.1.550/11529: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10113 Comm: syz.4.388 Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:cpu_is_isolated include/linux/sched/isolation.h:70 [inline] RIP: 0010:lookup_bh_lru fs/buffer.c:1366 [inline] RIP: 0010:__find_get_block+0x1a3/0x1150 fs/buffer.c:1400 Code: fa 4c 21 e3 75 07 e8 cc ea 74 ff eb 0a e8 c5 ea 74 ff e8 70 b3 7c ff e8 7b 16 9f 09 89 c3 89 c7 be 05 00 00 00 e8 3d d5 4e ff <84> c0 74 26 89 df be 04 00 00 00 e8 2d d5 4e ff 84 c0 74 1d 89 df RSP: 0000:ffffc9000529f480 EFLAGS: 00000082 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff819ca15c RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001 RBP: ffffc9000529f5b8 R08: ffffffff901bdd6f R09: 1ffffffff2037bad R10: dffffc0000000000 R11: fffffbfff2037bae R12: 0000000000000246 R13: dffffc0000000000 R14: 0000000000000200 R15: 0000000000000080 FS: 00007f8f070136c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa57dfbd000 CR3: 000000006934a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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_ent_get fs/exfat/fatent.c:48 [inline] exfat_ent_get+0x14d/0x400 fs/exfat/fatent.c:97 exfat_readdir fs/exfat/dir.c:187 [inline] exfat_iterate+0x1311/0x3390 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: 0033:0x7f8f0617e719 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:00007f8f07013038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f8f06335f80 RCX: 00007f8f0617e719 RDX: 0000000000000ff4 RSI: 00000000200001c0 RDI: 0000000000000007 RBP: 00007f8f061f139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8f06335f80 R15: 00007fff00ffa5c8