syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4421/1:b..l
	(detected by 1, t=10502 jiffies, g=10921, q=16 ncpus=2)
task:syz-executor.2  state:R  running task     stack:22120 pid:4421  ppid:3567   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6727
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 loop_queue_work drivers/block/loop.c:896 [inline]
 loop_queue_rq+0xa02/0xaf0 drivers/block/loop.c:1876
 __blk_mq_issue_directly block/blk-mq.c:2626 [inline]
 __blk_mq_try_issue_directly+0x4fe/0x820 block/blk-mq.c:2679
 blk_mq_try_issue_directly+0x28/0x1f0 block/blk-mq.c:2703
 blk_mq_submit_bio+0x162c/0x2590 block/blk-mq.c:3049
 __submit_bio+0x261/0x2f0 block/blk-core.c:590
 __submit_bio_noacct_mq block/blk-core.c:667 [inline]
 submit_bio_noacct_nocheck+0x976/0xd10 block/blk-core.c:696
 submit_bh fs/buffer.c:2707 [inline]
 __bread_slow fs/buffer.c:1177 [inline]
 __bread_gfp+0x1e8/0x370 fs/buffer.c:1370
 sb_bread_unmovable include/linux/buffer_head.h:344 [inline]
 ntfs_bread fs/ntfs3/fsntfs.c:994 [inline]
 ntfs_read_run_nb+0x599/0xf60 fs/ntfs3/fsntfs.c:1214
 ntfs_read_bh+0x3c/0x770 fs/ntfs3/fsntfs.c:1282
 mi_read+0x1e9/0x5a0 fs/ntfs3/record.c:133
 ntfs_read_mft fs/ntfs3/inode.c:69 [inline]
 ntfs_iget5+0x48a/0x3920 fs/ntfs3/inode.c:524
 dir_search_u+0x2f6/0x390 fs/ntfs3/dir.c:264
 ntfs_extend_init+0x191/0x530 fs/ntfs3/fsntfs.c:214
 ntfs_fill_super+0x407a/0x4410 fs/ntfs3/super.c:1243
 get_tree_bdev+0x3fe/0x620 fs/super.c:1355
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f414567f46a
RSP: 002b:00007f4146481ef8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f4146481f80 RCX: 00007f414567f46a
RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 00007f4146481f40
RBP: 0000000020000100 R08: 00007f4146481f80 R09: 000000000080c018
R10: 000000000080c018 R11: 0000000000000202 R12: 00000000200000c0
R13: 00007f4146481f40 R14: 000000000001f234 R15: 0000000020000140
 </TASK>
rcu: rcu_preempt kthread starved for 10511 jiffies! g10921 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:25528 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 4426 Comm: syz-executor.0 Not tainted 6.1.90-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5124
Code: 37 0b 00 48 83 c4 08 4c 89 f7 e8 98 30 00 00 0f 1f 44 00 00 4c 89 f7 e8 7b d0 35 09 e8 36 26 32 00 fb 49 8d bc 24 f8 15 00 00 <48> 89 f8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28
RSP: 0018:ffffc900036df388 EFLAGS: 00000282
RAX: 8966314565c04f00 RBX: ffff8880783d8034 RCX: ffffffff816acf0a
RDX: dffffc0000000000 RSI: ffffffff8aec01c0 RDI: ffff88807cd133b8
RBP: ffffc900036df3d0 R08: dffffc0000000000 R09: fffffbfff2093658
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807cd11dc0
R13: 1ffff110173276eb R14: ffff8880b993aa00 R15: ffff8880b993b758
FS:  0000555556769480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2aa492bf80 CR3: 000000007598f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 context_switch kernel/sched/core.c:5248 [inline]
 __schedule+0x1435/0x4550 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:kasan_check_range+0x5/0x290 mm/kasan/generic.c:188
Code: c7 e8 cf 71 a9 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 41 57 41 56 <53> b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 5a 02
RSP: 0018:ffffc900036df720 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff88807cd11dc0 RCX: ffffffff8a933c06
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88807cd11dc0
RBP: ffffc900036df7f8 R08: dffffc0000000000 R09: fffffbfff2093658
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920006dbef0
R13: 1ffff920006dbf0c R14: ffffffff8a933b59 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 test_ti_thread_flag include/linux/thread_info.h:118 [inline]
 need_resched include/linux/sched.h:2231 [inline]
 preempt_schedule_common+0xa6/0xd0 kernel/sched/core.c:6735
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:208
 unix_write_space+0x1fc/0x370 net/unix/af_unix.c:535
 sock_wfree+0x1b3/0x610 net/core/sock.c:2444
 unix_destruct_scm+0x2e3/0x350 net/unix/scm.c:152
 skb_release_head_state+0xf9/0x230 net/core/skbuff.c:843
 skb_release_all net/core/skbuff.c:854 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 kfree_skb_reason+0x13d/0x390 net/core/skbuff.c:893
 kfree_skb include/linux/skbuff.h:1220 [inline]
 unix_release_sock+0x99c/0xcf0 net/unix/af_unix.c:647
 unix_release+0x88/0xc0 net/unix/af_unix.c:1039
 __sock_release net/socket.c:654 [inline]
 sock_close+0xcd/0x230 net/socket.c:1400
 __fput+0x3b7/0x890 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2aa3c7cc5a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffc999e30e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f2aa3c7cc5a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f2aa3dad980 R08: 0000001b31f20000 R09: 000000000000008b
R10: 00000000818e5ae0 R11: 0000000000000293 R12: 00000000000187d0
R13: 00007f2aa3dac12c R14: 00007f2aa3dac120 R15: 0000000000000032
 </TASK>