syzbot

INFO: task syz-executor413:5827 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor413 state:D stack:28888 pid:5827  tgid:5821  ppid:5820   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 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_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
 inode_lock_nested include/linux/fs.h:902 [inline]
 lock_rename fs/namei.c:3265 [inline]
 do_renameat2+0x3dd/0xc50 fs/namei.c:5216
 __do_sys_rename fs/namei.c:5317 [inline]
 __se_sys_rename fs/namei.c:5315 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5315
 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: 0033:0x7f4d09f58409
RSP: 002b:00007f4d09eeb168 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f4d09fdf6b8 RCX: 00007f4d09f58409
RDX: 00007f4d09f31b56 RSI: 00002000000002c0 RDI: 0000200000000580
RBP: 00007f4d09fdf6b0 R08: 00007ffea48d8be7 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d09fdf6bc
R13: 000000000000006e R14: 00007ffea48d8b00 R15: 00007ffea48d8be8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5574:
 #0: ffff888034aa20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor413/5823:
2 locks held by syz-executor413/5827:
 #0: ffff88802c30a420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff88807bcfabd8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
 #1: ffff88807bcfabd8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3265 [inline]
 #1: ffff88807bcfabd8 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: do_renameat2+0x3dd/0xc50 fs/namei.c:5216

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5823 Comm: syz-executor413 Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_preemption_disabled+0x3/0x120 lib/smp_processor_id.c:13
Code: c0 8b 48 c7 c6 c0 fe c0 8b eb 1c 66 66 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 55 41 57 <41> 56 53 48 83 ec 10 65 48 8b 05 4e ee 22 07 48 89 44 24 08 65 8b
RSP: 0018:ffffc90003fa6f88 EFLAGS: 00000046
RAX: 98d0f4957106d9ef RBX: 0000000000000202 RCX: cd0dc5490b8a1b00
RDX: 0000000000000003 RSI: ffffffff8d9213f3 RDI: ffffffff8bc0fee0
RBP: ffff88807d4f0b68 R08: ffff88807bccf1df R09: 1ffff1100f799e3b
R10: dffffc0000000000 R11: ffffed100f799e3c R12: 0000000000000003
R13: 0000000000000003 R14: ffff88807bccee40 R15: ffff88807d4f0000
FS:  00007f4d09f0c6c0(0000) GS:ffff888126200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055de28bfa168 CR3: 000000002732c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lockdep_recursion_finish kernel/locking/lockdep.c:472 [inline]
 lock_release+0x27a/0x3e0 kernel/locking/lockdep.c:5889
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5209 [inline]
 ext4_mark_iloc_dirty+0x55a/0x1ca0 fs/ext4/inode.c:5869
 __ext4_mark_inode_dirty+0x4be/0x700 fs/ext4/inode.c:6074
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6103
 __mark_inode_dirty+0x2ce/0xdf0 fs/fs-writeback.c:2527
 mark_inode_dirty include/linux/fs.h:2545 [inline]
 dquot_alloc_space include/linux/quotaops.h:319 [inline]
 dquot_alloc_block include/linux/quotaops.h:336 [inline]
 ext4_xattr_block_set+0x12ca/0x2ac0 fs/ext4/xattr.c:2048
 ext4_xattr_set_handle+0xdfb/0x1590 fs/ext4/xattr.c:2447
 ext4_initxattrs+0x9f/0x110 fs/ext4/xattr_security.c:44
 security_inode_init_security+0x29d/0x3f0 security/security.c:1852
 __ext4_new_inode+0x3257/0x3bd0 fs/ext4/ialloc.c:1326
 ext4_create+0x22d/0x460 fs/ext4/namei.c:2824
 lookup_open fs/namei.c:3701 [inline]
 open_last_lookups fs/namei.c:3800 [inline]
 path_openat+0x14f1/0x3830 fs/namei.c:4036
 do_filp_open+0x1fa/0x410 fs/namei.c:4066
 do_sys_openat2+0x121/0x1c0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_creat fs/open.c:1522 [inline]
 __se_sys_creat fs/open.c:1516 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1516
 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: 0033:0x7f4d09f58409
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4d09f0c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f4d09fdf6a8 RCX: 00007f4d09f58409
RDX: ffffffffffffffb0 RSI: 0000000000000182 RDI: 0000200000000000
RBP: 00007f4d09fdf6a0 R08: 00007f4d09f0c6c0 R09: 0000000000000000
R10: 00007f4d09f0c6c0 R11: 0000000000000246 R12: 00007f4d09fdf6ac
R13: 0000000000000006 R14: 00007ffea48d8b00 R15: 00007ffea48d8be8
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.341 msecs