INFO: task syz.6.3835:23809 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.3835 state:D stack:22328 pid:23809 tgid:23767 ppid:21971 task_flags:0x440140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5254 [inline] __schedule+0x17c4/0x4d60 kernel/sched/core.c:6862 __schedule_loop kernel/sched/core.c:6944 [inline] schedule+0x165/0x360 kernel/sched/core.c:6959 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 ___down_common kernel/locking/semaphore.c:268 [inline] __down_common+0x319/0x6a0 kernel/locking/semaphore.c:293 down+0x80/0xd0 kernel/locking/semaphore.c:100 xfs_buf_lock+0x15d/0x4d0 fs/xfs/xfs_buf.c:993 xfs_buf_find_lock+0x42/0x4c0 fs/xfs/xfs_buf.c:419 xfs_buf_lookup fs/xfs/xfs_buf.c:472 [inline] xfs_buf_get_map+0x10cf/0x1840 fs/xfs/xfs_buf.c:594 xfs_buf_read_map+0x82/0xa50 fs/xfs/xfs_buf.c:699 xfs_trans_read_buf_map+0x1d7/0x8e0 fs/xfs/xfs_trans_buf.c:304 xfs_trans_read_buf fs/xfs/xfs_trans.h:210 [inline] xfs_read_agf+0x281/0x5c0 fs/xfs/libxfs/xfs_alloc.c:3376 xfs_alloc_read_agf+0x17c/0xb70 fs/xfs/libxfs/xfs_alloc.c:3411 xfs_alloc_fix_freelist+0x60a/0x1300 fs/xfs/libxfs/xfs_alloc.c:2875 xfs_alloc_vextent_prepare_ag+0xdb/0x610 fs/xfs/libxfs/xfs_alloc.c:3566 xfs_alloc_vextent_iterate_ags+0x140/0x940 fs/xfs/libxfs/xfs_alloc.c:3750 xfs_alloc_vextent_start_ag+0x388/0x850 fs/xfs/libxfs/xfs_alloc.c:3839 xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3619 [inline] xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3663 [inline] xfs_bmapi_allocate+0x188e/0x2e00 fs/xfs/libxfs/xfs_bmap.c:3938 xfs_bmapi_write+0x7df/0x1260 fs/xfs/libxfs/xfs_bmap.c:4267 xfs_attr_rmtval_set_blk+0x15b/0x320 fs/xfs/libxfs/xfs_attr_remote.c:640 xfs_attr_rmtval_alloc fs/xfs/libxfs/xfs_attr.c:637 [inline] xfs_attr_set_iter+0x2d4/0x4b70 fs/xfs/libxfs/xfs_attr.c:866 xfs_attr_finish_item+0xed/0x320 fs/xfs/xfs_attr_item.c:506 xfs_defer_finish_one+0x5c8/0xcf0 fs/xfs/libxfs/xfs_defer.c:595 xfs_defer_finish_noroll+0x910/0x12d0 fs/xfs/libxfs/xfs_defer.c:707 xfs_trans_commit+0x10b/0x1c0 fs/xfs/xfs_trans.c:921 xfs_attr_set+0xdc6/0x1210 fs/xfs/libxfs/xfs_attr.c:1150 xfs_xattr_set+0x14d/0x250 fs/xfs/xfs_xattr.c:186 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321 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/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f501238efc9 RSP: 002b:00007f50131c9038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 00007f50125e6270 RCX: 00007f501238efc9 RDX: 00002000000013c0 RSI: 0000200000000140 RDI: 0000200000000100 RBP: 00007f5012411f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f50125e6308 R14: 00007f50125e6270 R15: 00007ffe4f301168 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5591: #0: ffff88802fb8e0a0 (&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 4 locks held by syz.6.3835/23808: #0: ffff8880312c4420 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508 #1: ffff88806a2aa130 (&inode->i_sb->s_type->i_mutex_dir_key){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #1: ffff88806a2aa130 (&inode->i_sb->s_type->i_mutex_dir_key){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 #2: ffff8880312c4610 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc+0xd7/0x980 fs/xfs/xfs_trans.c:256 #3: ffff88806a2a9f18 (&xfs_dir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1082 4 locks held by syz.6.3835/23809: #0: ffff8880312c4420 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508 #1: ffff88806e2319b0 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #1: ffff88806e2319b0 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320 #2: ffff8880312c4610 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc+0xd7/0x980 fs/xfs/xfs_trans.c:256 #3: ffff88806e231798 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1082 1 lock held by syz-executor/23965: #0: ffffffff8e1431b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8e1431b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 1 lock held by syz.2.4263/25576: #0: ffff88805988c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88805988c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88805988c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 1 lock held by syz.2.4263/25577: #0: ffffffff8e143080 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820 1 lock held by syz.2.4263/25578: #0: ffff88806ce0e0e0 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x930 fs/super.c:344 ============================================= 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 10/02/2025 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:337 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:500 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 19057 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x102/0x130 kernel/kcov.c:-1 Code: 48 c1 e3 05 4c 8d 63 28 4d 39 fc 77 9d 49 ff c6 4d 89 33 49 89 4c 1b 08 4d 89 54 1b 10 49 89 7c 1b 18 49 89 54 1b 20 eb 81 5b <41> 5c 41 5e 41 5f e9 03 28 91 09 cc b9 05 00 00 00 48 85 c0 0f 85 RSP: 0018:ffffc9000d3d7dc0 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88807bab8000 RCX: 0000000000000005 RDX: ffffffff823a7a10 RSI: ffffffff8e28a400 RDI: 0000000000000001 RBP: 0000000000000040 R08: ffff888055ab3c80 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff88807bab8010 R15: 0000000000000001 FS: 000055556f52f500(0000) GS:ffff888125dfd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556f562688 CR3: 000000004899c000 CR4: 00000000003526f0 Call Trace: putname+0x80/0x190 fs/namei.c:285 user_path_at+0x44/0x60 fs/namei.c:3217 ksys_umount fs/namespace.c:2061 [inline] __do_sys_umount fs/namespace.c:2069 [inline] __se_sys_umount fs/namespace.c:2067 [inline] __x64_sys_umount+0xee/0x160 fs/namespace.c:2067 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3177b902f7 Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffe0b714518 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3177b902f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe0b7145d0 RBP: 00007ffe0b7145d0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe0b715660 R13: 00007f3177c11d7d R14: 00000000001731b3 R15: 00007ffe0b7156a0