rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4323/1:b..l
(detected by 0, t=10502 jiffies, g=5441, q=126)
task:udevd state:R running task stack:25888 pid: 4323 ppid: 3561 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:413 [inline]
loop_queue_work drivers/block/loop.c:1069 [inline]
loop_queue_rq+0x9e0/0xac0 drivers/block/loop.c:2202
__blk_mq_issue_directly block/blk-mq.c:2014 [inline]
__blk_mq_try_issue_directly+0x497/0x810 block/blk-mq.c:2070
blk_mq_request_issue_directly block/blk-mq.c:2118 [inline]
blk_mq_try_issue_list_directly+0x1a1/0x530 block/blk-mq.c:2136
blk_mq_sched_insert_requests+0x2d6/0x5c0 block/blk-mq-sched.c:512
blk_mq_flush_plug_list+0x57f/0x660 block/blk-mq.c:1971
blk_flush_plug_list+0x3ec/0x430 block/blk-core.c:1734
blk_finish_plug+0x59/0x80 block/blk-core.c:1751
read_pages+0x4c2/0x920 mm/readahead.c:150
page_cache_ra_unbounded+0x830/0x930 mm/readahead.c:239
do_page_cache_ra mm/readahead.c:269 [inline]
force_page_cache_ra+0x3e5/0x440 mm/readahead.c:301
page_cache_sync_readahead include/linux/pagemap.h:833 [inline]
filemap_get_pages mm/filemap.c:2551 [inline]
filemap_read+0x589/0x2480 mm/filemap.c:2634
blkdev_read_iter+0x11d/0x150 block/fops.c:563
call_read_iter include/linux/fs.h:2166 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x725/0xcf0 fs/read_write.c:485
ksys_read+0x14d/0x250 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb629b42407
RSP: 002b:00007ffc34dd87f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fb629a54880 RCX: 00007fb629b42407
RDX: 0000000000000200 RSI: 00007fb62910a000 RDI: 0000000000000009
RBP: 000055f79562c050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 000055f795638db8 R15: 00007fb62a29839c
rcu: rcu_preempt kthread starved for 10523 jiffies! g5441 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:I stack:27656 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4333 Comm: syz.0.8 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969
Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 66 49 0b 00 83 e3 01 75 07 e8 fc 45 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7
RSP: 0018:ffffc900011ff8c0 EFLAGS: 00000246
RAX: ffffffff816c84db RBX: 0000000000000001 RCX: 0000000000080000
RDX: ffffc90003e01000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900011ff9f0 R08: dffffc0000000000 R09: fffffbfff1ff763b
R10: fffffbfff1ff763b R11: 1ffffffff1ff763a R12: ffff8880b9042a08
R13: 1ffff11017208541 R14: ffff8880b913b380 R15: 0000000000000000
FS: 00007f2357f446c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b325ffff8 CR3: 000000002ab69000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
kill_bdev block/bdev.c:76 [inline]
set_blocksize+0x2eb/0x370 block/bdev.c:157
sb_set_blocksize+0x45/0xe0 block/bdev.c:166
udf_load_vrs+0x85/0xad0 fs/udf/super.c:2016
udf_fill_super+0x69f/0x18f0 fs/udf/super.c:2220
mount_bdev+0x287/0x3c0 fs/super.c:1400
legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
vfs_get_tree+0x88/0x270 fs/super.c:1530
do_new_mount+0x24a/0xa40 fs/namespace.c:3025
do_mount fs/namespace.c:3368 [inline]
__do_sys_mount fs/namespace.c:3576 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3553
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2359cde38a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2357f43e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f2357f43ef0 RCX: 00007f2359cde38a
RDX: 0000200000000000 RSI: 0000200000000c80 RDI: 00007f2357f43eb0
RBP: 0000200000000000 R08: 00007f2357f43ef0 R09: 0000000000000048
R10: 0000000000000048 R11: 0000000000000246 R12: 0000200000000c80
R13: 00007f2357f43eb0 R14: 0000000000000c24 R15: 0000200000001980