rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12334/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=43057, q=155 ncpus=2)
task:syz.2.1265 state:R running task stack:26376 pid:12334 tgid:12331 ppid:5815 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
irqentry_exit+0x36/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: 87 0b 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 a2 20 ea 0e 0f 82 74 02 00 00 8b 35 1a 51 ea 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 b9 86 0b 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9001bc3ec58 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c4460 RCX: 000000009c6af5eb
RDX: 0000000000000000 RSI: ffffffff8dade5b8 RDI: ffffffff8bf1ea40
RBP: 0000000000000002 R08: 04c458fa08cd7175 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__set_page_owner+0x91/0x550 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850
prep_new_page mm/page_alloc.c:1858 [inline]
get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884
__alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2435
vma_alloc_folio_noprof+0xed/0x1e0 mm/mempolicy.c:2470
folio_prealloc mm/memory.c:1189 [inline]
wp_page_copy mm/memory.c:3679 [inline]
do_wp_page+0x11d8/0x52b0 mm/memory.c:4140
handle_pte_fault mm/memory.c:6193 [inline]
__handle_mm_fault+0x1ae3/0x2aa0 mm/memory.c:6318
handle_mm_fault+0x589/0xd10 mm/memory.c:6487
do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 d1 82 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9001bc3f9e8 EFLAGS: 00050246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000020000027c030
RDX: 0000000000080000 RSI: ffffffff892e5833 RDI: 0000000000000005
RBP: ffffc9001bc3fd88 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: 000020000027c000 R14: ffffc9001bc3fdcc R15: 0000000000000002
____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2863
___sys_recvmsg+0x114/0x1a0 net/socket.c:2892
do_recvmmsg+0x2fe/0x750 net/socket.c:2987
__sys_recvmmsg net/socket.c:3061 [inline]
__do_sys_recvmmsg net/socket.c:3084 [inline]
__se_sys_recvmmsg net/socket.c:3077 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3077
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd2b1f8efc9
RSP: 002b:00007fd2b2e6d038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fd2b21e6090 RCX: 00007fd2b1f8efc9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007fd2b2011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd2b21e6128 R14: 00007fd2b21e6090 R15: 00007ffd22d44df8
rcu: rcu_preempt kthread timer wakeup didn't happen for 10554 jiffies! g43057 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=57693
rcu: rcu_preempt kthread starved for 10555 jiffies! g43057 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28080 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 1297 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 a6 d7 2f f6 48 89 df e8 8e 2b 30 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 45 36 20 f6 65 8b 05 7e 65 3b 08 85 c0 74 16 5b
RSP: 0018:ffffc900045df968 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9ae0b320 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8db03f74 RDI: ffffffff8bf1ea40
RBP: 0000000000000293 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff908339d7 R11: 0000000000000001 R12: ffffffff9ae0b428
R13: 0000000000000003 R14: 0000000000000001 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff8881249d6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd17ff8 CR3: 000000005d146000 CR4: 00000000003526f0
Call Trace:
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline]
uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline]
uart_write+0x4c1/0xb30 drivers/tty/serial/serial_core.c:626
handle_tx+0x204/0x630 drivers/net/caif/caif_serial.c:222
__netdev_start_xmit include/linux/netdevice.h:5248 [inline]
netdev_start_xmit include/linux/netdevice.h:5257 [inline]
xmit_one net/core/dev.c:3845 [inline]
dev_hard_start_xmit+0x97/0x740 net/core/dev.c:3861
__dev_queue_xmit+0xa46/0x4490 net/core/dev.c:4763
dev_queue_xmit include/linux/netdevice.h:3365 [inline]
tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62
kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245