INFO: task syz.8.2098:14574 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.2098 state:D stack:28936 pid:14574 tgid:14538 ppid:12599 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 inode_lock include/linux/fs.h:870 [inline] vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x274/0x600 fs/xattr.c:665 path_setxattrat+0x364/0x3a0 fs/xattr.c:713 __do_sys_setxattr fs/xattr.c:747 [inline] __se_sys_setxattr fs/xattr.c:743 [inline] __x64_sys_setxattr+0xbc/0xe0 fs/xattr.c:743 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb066f8eba9 RSP: 002b:00007fb067dc2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 00007fb0671d6090 RCX: 00007fb066f8eba9 RDX: 00002000000002c0 RSI: 0000200000000140 RDI: 0000200000000100 RBP: 00007fb067011e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb0671d6128 R14: 00007fb0671d6090 R15: 00007ffd77e95cb8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5616: #0: ffff8880337460a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 6 locks held by kworker/0:1/9787: #0: ffff888020ebf548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888020ebf548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9001e587bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9001e587bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888028225198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #2: ffff888028225198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888143fe8518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff888143fe8518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff888143fe8518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff888143fe8518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #3: ffff888143fe8518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20 drivers/usb/core/hub.c:5952 #4: ffff8880276dc968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8880276dc968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8880276dc968 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #4: ffff8880276dc968 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952 #5: ffffffff8ede11f0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750 drivers/usb/core/hub.c:3066 3 locks held by kworker/u9:0/11778: #0: ffff888054c23148 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888054c23148 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90003f3fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003f3fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888032a34dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 4 locks held by syz.8.2098/14539: #0: ffff8880234fa428 (sb_writers#31){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff8880528d6fb0 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #1: ffff8880528d6fb0 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 #2: ffff8880234fa618 (sb_internal#4){.+.+}-{0:0}, at: xfs_trans_alloc+0xd7/0x980 fs/xfs/xfs_trans.c:256 #3: ffff8880528d6d98 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1081 2 locks held by syz.8.2098/14574: #0: ffff8880234fa428 (sb_writers#31){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff8880528d6fb0 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #1: ffff8880528d6fb0 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 2 locks held by syz-executor/14721: #0: ffffffff8e88ee08 (bio_slab_lock){+.+.}-{4:4}, at: bio_put_slab block/bio.c:140 [inline] #0: ffffffff8e88ee08 (bio_slab_lock){+.+.}-{4:4}, at: bioset_exit+0x44a/0x690 block/bio.c:1764 #1: ffffffff8e13f880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3815 2 locks held by syz.2.2569/16251: #0: ffff8880560360e0 (&type->s_umount_key#64/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345 #1: ffffffff8e13f880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3815 7 locks held by syz.0.2582/16305: #0: ffffffff8e12e1c0 (console_lock){+.+.}-{0:0}, at: do_fb_ioctl+0x583/0x750 drivers/video/fbdev/core/fb_chrdev.c:86 #1: ffff8880248f3078 (&fb_info->lock){+.+.}-{4:4}, at: lock_fb_info include/linux/fb.h:623 [inline] #1: ffff8880248f3078 (&fb_info->lock){+.+.}-{4:4}, at: do_fb_ioctl+0x598/0x750 drivers/video/fbdev/core/fb_chrdev.c:87 #2: ffff8881446c5a80 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_pan_display+0xbe/0xbd0 drivers/gpu/drm/drm_fb_helper.c:1441 #3: ffff8880248521b8 (&dev->master_mutex){+.+.}-{4:4}, at: drm_master_internal_acquire+0x20/0x80 drivers/gpu/drm/drm_auth.c:435 #4: ffff8881446c5898 (&client->modeset_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_locked+0x4c/0x4d0 drivers/gpu/drm/drm_client_modeset.c:1204 #5: ffffc9001dadf690 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xda/0x760 drivers/gpu/drm/drm_client_modeset.c:1042 #6: ffffc9001dadf6b8 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_atomic+0xda/0x760 drivers/gpu/drm/drm_client_modeset.c:1042 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5237 Code: 48 c7 c7 7e 7a ba 8d 48 c7 c6 76 c9 a9 8d e8 9b de e5 ff 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 48 83 78 40 00 0f 84 6a 01 00 00 <4c> 89 f6 89 ea 4c 89 f9 e8 17 38 00 00 85 c0 0f 84 e4 01 00 00 41 RSP: 0018:ffffc90000127880 EFLAGS: 00000086 RAX: ffffffff93497888 RBX: 0000000000000002 RCX: 000000003cb19ffd RDX: 0000000048dd1c3c RSI: 00000000189d2709 RDI: ffff88801ceb8000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8b48283a R10: dffffc0000000000 R11: fffffbfff1f47427 R12: 00000000e9591a06 R13: ffff88801ceb8af0 R14: ffff88801ceb8b40 R15: 444d79323cb19ffd FS: 0000000000000000(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fba2d3056c0 CR3: 000000000df36000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_process_nc_paths+0xdb/0x3a0 net/batman-adv/network-coding.c:687 batadv_nc_worker+0x429/0x610 net/batman-adv/network-coding.c:728 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245