rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9/1:b..l
(detected by 1, t=10502 jiffies, g=43953, q=43)
task:kworker/u4:0 state:R running task stack:21896 pid: 9 ppid: 2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:8)
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90000ce6c08 EFLAGS: 00000206
RAX: ef66d3c35a7e3700 RBX: ffff88813fed0000 RCX: ef66d3c35a7e3700
RDX: 0000000000000000 RSI: ffffffff8a0b2460 RDI: ffffffff8a59a740
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffff940002e4957
R10: fffff940002e4957 R11: 1ffffd40002e4956 R12: 0000000000000003
R13: 0000000000000246 R14: ffffffff8c11bfa0 R15: ffff88813fed0b68
xa_entry include/linux/xarray.h:1182 [inline]
xas_find_marked+0x742/0x1010 lib/xarray.c:1365
find_get_entry+0x6b/0x270 mm/filemap.c:1980
find_get_pages_range_tag+0x199/0x450 mm/filemap.c:2272
pagevec_lookup_range_tag+0x36/0x80 mm/swap.c:1114
mpage_prepare_extent_to_map+0x339/0xf70 fs/ext4/inode.c:2590
ext4_writepages+0xe86/0x2d20 fs/ext4/inode.c:2827
do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386
__writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1647
writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1930
wb_writeback+0x443/0xb90 fs/fs-writeback.c:2104
wb_do_writeback fs/fs-writeback.c:2247 [inline]
wb_workfn+0x423/0xe60 fs/fs-writeback.c:2288
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: rcu_preempt kthread starved for 10543 jiffies! g43953 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:28128 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10209 Comm: syz.7.1403 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x80 kernel/kcov.c:294
Code: 28 4d 39 ca 77 22 89 ff 89 f6 4a c7 44 02 08 03 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 <48> 8b 04 24 65 48 8b 0d 34 aa 8a 7e 65 8b 15 35 aa 8a 7e 81 e2 00
RSP: 0018:ffffc9000301fed8 EFLAGS: 00000046
RAX: ffffffff819cc622 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000e54c000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: ffffc9000301ff48 R08: dffffc0000000000 R09: fffffbfff1ad157e
R10: fffffbfff1ad157e R11: 1ffffffff1ad157d R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000301ff58 R15: 0000000000000000
FS: 00007f43c58326c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 000000007d575000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
cpu_max_bits_warn include/linux/cpumask.h:108 [inline]
cpumask_check include/linux/cpumask.h:115 [inline]
cpumask_test_cpu include/linux/cpumask.h:344 [inline]
cpu_online include/linux/cpumask.h:895 [inline]
trace_user_exit+0x25/0x190 include/trace/events/context_tracking.h:48
__context_tracking_exit+0x51/0x80 kernel/context_tracking.c:161
user_exit_irqoff include/linux/context_tracking.h:47 [inline]
__enter_from_user_mode kernel/entry/common.c:22 [inline]
syscall_enter_from_user_mode+0x56/0x70 kernel/entry/common.c:110
do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f43c79c18e7
Code: 0b e9 68 fe ff ff 48 83 c4 18 48 8d 3d b2 6f d6 00 5b 5d 41 5c 41 5d 41 5e 41 5f e9 13 f8 fb ff 0f 1f 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00
RSP: 002b:00007f43c5831b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007f43c5831c70 RCX: 00007f43c79c18e7
RDX: 00007f43c5831b40 RSI: 00007f43c5831c70 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f43c7bf1fac
R13: 0000000000000000 R14: 00007fff27bcbb10 R15: 00007fff27bcbbf8