INFO: task syz.1.53:6230 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00051-g405e6c37c89e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.53 state:D stack:27904 pid:6230 tgid:6196 ppid:5819 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [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_lsetxattr fs/xattr.c:754 [inline] __se_sys_lsetxattr fs/xattr.c:750 [inline] __x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:750 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f785838e969 RSP: 002b:00007f78591d2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007f78585b6160 RCX: 00007f785838e969 RDX: 0000200000000340 RSI: 0000200000000180 RDI: 0000200000000040 RBP: 00007f7858410ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000000d4 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f78585b6160 R15: 00007ffccbf67fc8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/u8:3/54: #0: ffff88801afce948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801afce948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000120fc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000120fc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 2 locks held by kworker/u8:5/1030: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:613 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 2 locks held by getty/5577: #0: ffff88802fef20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900030062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5833: #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 4 locks held by syz.1.53/6198: #0: ffff8880110b0420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880781da230 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880781da230 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 #2: ffff8880110b0610 (sb_internal#3){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1096 #3: ffff8880781da018 (&xfs_nondir_ilock_class){+.+.}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1102 2 locks held by syz.1.53/6230: #0: ffff8880110b0420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff8880781da230 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880781da230 (&sb->s_type->i_mutex_key#26){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 1 lock held by dhcpcd-run-hook/7940: #0: ffff888031789868 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_read+0xd14/0x1040 fs/pipe.c:393 1 lock held by dhcpcd-run-hook/7954: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:613 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00051-g405e6c37c89e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 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: 54 Comm: kworker/u8:3 Not tainted 6.15.0-rc6-syzkaller-00051-g405e6c37c89e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x17/0xb0 kernel/rcu/tree.c:736 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 a0 76 ce 10 e8 fb 47 af 09 89 c3 <83> f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 20 fc 96 RSP: 0018:ffffc9000120fa00 EFLAGS: 00000286 RAX: 0000000000000001 RBX: 0000000000000001 RCX: c7a91856fb692c00 RDX: 0000000000000000 RSI: ffffffff8bc1d800 RDI: ffffffff8bc1d7c0 RBP: ffffffff8b243dc2 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8b243dc2 R12: 0000000000000002 R13: ffffffff8df3dce0 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881261c7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3d8c913000 CR3: 0000000031aef000 CR4: 0000000000350ef0 Call Trace: trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5829 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245