syzbot

INFO: task syz.4.86:5598 blocked for more than 143 seconds.
      Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.86        state:D stack:26224 pid:5598  tgid:5593  ppid:5220   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6621
 io_schedule+0xbf/0x130 kernel/sched/core.c:7401
 folio_wait_bit_common+0x3d8/0x9b0 mm/filemap.c:1307
 folio_lock include/linux/pagemap.h:1050 [inline]
 invalidate_inode_pages2_range+0x8be/0x1230 mm/truncate.c:639
 kiocb_invalidate_pages+0x10e/0x180 mm/filemap.c:2738
 blkdev_direct_write block/fops.c:648 [inline]
 blkdev_write_iter+0x441/0xc20 block/fops.c:713
 iter_file_splice_write+0x906/0x10b0 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x19b/0x6d0 fs/splice.c:1164
 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x17e/0x250 fs/splice.c:1233
 do_sendfile+0xb1e/0xe50 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x1da/0x220 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde5bb799f9
RSP: 002b:00007fde5c939038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fde5bd16130 RCX: 00007fde5bb799f9
RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000007
RBP: 00007fde5bbe78ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000100000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fde5bd16130 R15: 00007ffce67afc98
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8ddb5ce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #0: ffffffff8ddb5ce0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8ddb5ce0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626
5 locks held by kworker/u8:7/1063:
2 locks held by getty/4976:
 #0: ffff88802b3a70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5225:
2 locks held by kworker/0:3/5275:
 #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206
 #1: ffffc9000368fd80 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207
2 locks held by syz.2.57/5499:
2 locks held by kworker/u8:10/5899:
 #0: ffff88801a702948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206
 #1: ffffc9000377fd80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207
2 locks held by syz.2.247/6355:
 #0: ffff88804fea60e0 (&type->s_umount_key#68){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88804fea60e0 (&type->s_umount_key#68){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88804fea60e0 (&type->s_umount_key#68){+.+.}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:505
 #1: ffffffff8ddc1478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328
1 lock held by syz.3.251/6359:
 #0: ffffffff8ddc1478 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf4e/0x1280 kernel/hung_task.c:379
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111