rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26204/1:b..l P26206/1:b..l P26195/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=127197, q=198 ncpus=2)
task:syz.8.4925 state:R running task stack:26408 pid:26195 tgid:26191 ppid:19614 task_flags:0x400040 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6966
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
wp_page_copy mm/memory.c:3670 [inline]
do_wp_page+0x177b/0x4f20 mm/memory.c:4030
handle_pte_fault mm/memory.c:6085 [inline]
__handle_mm_fault+0x2223/0x5490 mm/memory.c:6212
handle_mm_fault+0x589/0xd10 mm/memory.c:6381
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+0x5c/0xb0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
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 11 5b 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000455f9f8 EFLAGS: 00050246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000121030
RDX: 0000000000080000 RSI: ffffffff89564373 RDI: 0000000000000005
RBP: ffffc9000455fd98 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000001 R12: 0000000000000000
R13: 0000200000121000 R14: ffffc9000455fddc R15: 0000000000000002
____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2799
___sys_recvmsg+0x114/0x1a0 net/socket.c:2828
do_recvmmsg+0x2fe/0x750 net/socket.c:2923
__sys_recvmmsg net/socket.c:2997 [inline]
__do_sys_recvmmsg net/socket.c:3020 [inline]
__se_sys_recvmmsg net/socket.c:3013 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f99c1d8e929
RSP: 002b:00007f99c2b65038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f99c1fb6080 RCX: 00007f99c1d8e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f99c1e10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f99c1fb6080 R15: 00007ffdc56b41c8
task:syz.9.4927 state:R running task stack:27672 pid:26206 tgid:26201 ppid:22062 task_flags:0x40044c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:rcu_is_watching+0x0/0xc0 kernel/rcu/tree.c:741
Code: f4 5c 8e e8 d2 03 6d 03 e9 51 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 53 65 ff 05 e3 65 2f 12 e8 be fa e6 09 48 c7 c3 28
RSP: 0018:ffffc9000454f518 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 00007f6b90e88000 RCX: ffffffff820e6c28
RDX: ffff888026ae8000 RSI: ffffffff820e6e63 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffc9000454f590
R13: ffff888084148438 R14: ffffc9000454f750 R15: 00007f6b90e88000
rcu_read_lock include/linux/rcupdate.h:842 [inline]
___pte_offset_map+0x298/0x570 mm/pgtable-generic.c:287
__pte_offset_map include/linux/mm.h:3000 [inline]
__pte_offset_map_lock+0x8d/0x310 mm/pgtable-generic.c:398
pte_offset_map_lock include/linux/mm.h:3015 [inline]
zap_pte_range mm/memory.c:1721 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0xbc3/0x4350 mm/memory.c:1898
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:1941
unmap_vmas+0x218/0x470 mm/memory.c:1985
exit_mmap+0x1b9/0xb90 mm/mmap.c:1284
__mmput+0x12a/0x410 kernel/fork.c:1121
mmput+0x62/0x70 kernel/fork.c:1144
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7c4/0x2bd0 kernel/exit.c:952
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b9218e929
RSP: 002b:00007f6b930950e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f6b923b6168 RCX: 00007f6b9218e929
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6b923b6168
RBP: 00007f6b923b6160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b923b616c
R13: 0000000000000000 R14: 00007ffc4b9b74b0 R15: 00007ffc4b9b7598
task:modprobe state:R running task stack:25512 pid:26204 tgid:26204 ppid:3594 task_flags:0x40000c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
RIP: 0010:stack_access_ok+0x53/0x200 arch/x86/kernel/unwind_orc.c:393
Code: 83 ec 08 80 3c 02 00 0f 85 94 01 00 00 4c 8d 6b 10 4c 8b 7b 08 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 <0f> 85 52 01 00 00 48 89 da 48 8b 4b 10 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc900047c7168 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffc900047c7218 RCX: ffffffff914ce85c
RDX: 1ffff920008f8e45 RSI: ffffc900047c7958 RDI: ffffc900047c7218
RBP: ffffc900047c7958 R08: ffffffff914ce860 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000011f49 R12: 0000000000000008
R13: ffffc900047c7228 R14: ffffc900047c7220 R15: ffffc900047c0000
deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
unwind_next_frame+0xb7d/0x20a0 arch/x86/kernel/unwind_orc.c:585
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:1704
prep_new_page mm/page_alloc.c:1712 [inline]
get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
__alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
alloc_frozen_pages_noprof mm/mempolicy.c:2490 [inline]
alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2510
get_free_pages_noprof+0x10/0xb0 mm/page_alloc.c:5018
tlb_remove_table+0x36e/0xa80 mm/mmu_gather.c:367
__pte_free_tlb arch/x86/include/asm/pgalloc.h:59 [inline]
free_pte_range mm/memory.c:176 [inline]
free_pmd_range mm/memory.c:194 [inline]
free_pud_range mm/memory.c:228 [inline]
free_p4d_range mm/memory.c:262 [inline]
free_pgd_range+0x7ee/0x12e0 mm/memory.c:351
free_pgtables+0x25f/0xcb0 mm/memory.c:406
exit_mmap+0x3fb/0xb90 mm/mmap.c:1295
__mmput+0x12a/0x410 kernel/fork.c:1121
mmput+0x62/0x70 kernel/fork.c:1144
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7c4/0x2bd0 kernel/exit.c:952
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
__do_sys_exit_group kernel/exit.c:1116 [inline]
__se_sys_exit_group kernel/exit.c:1114 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1114
x64_sys_call+0x1530/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60f447d6c5
RSP: 002b:00007fffdb7af658 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f60f457efe8 RCX: 00007f60f447d6c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001
RBP: 0000000000000001 R08: 00007fffdb7af5e8 R09: 0000000000000000
R10: 00007fffdb7af480 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f60f457d680 R15: 00007f60f457f000
rcu: rcu_preempt kthread timer wakeup didn't happen for 10625 jiffies! g127197 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=115615
rcu: rcu_preempt kthread starved for 10626 jiffies! g127197 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:26744 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6879
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1296 Comm: aoe_tx0 Not tainted 6.16.0-rc5-syzkaller-00276-g5d5d62298b8b #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:iterate_chain_key kernel/locking/lockdep.c:454 [inline]
RIP: 0010:__lock_acquire+0x65f/0x1c90 kernel/locking/lockdep.c:5228
Code: 10 8b 74 24 18 44 8b 74 24 28 c1 e0 0d 66 0b 04 24 98 29 f0 8b 74 24 20 31 f0 89 c2 41 29 c6 01 c8 c1 c2 06 41 31 d6 44 89 f2 <44> 29 f1 41 01 c6 c1 c2 08 31 d1 89 ca 29 c8 44 01 f1 c1 c2 10 89
RSP: 0018:ffffc900050cf838 EFLAGS: 00000086
RAX: 00000000703c423b RBX: 0000000000000002 RCX: 0000000064326dcf
RDX: 00000000a1dab7e8 RSI: 00000000478ec78b RDI: ffff8880290fd3c0
RBP: ffff8880290fc880 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880290fd370
R13: ffff8880290fd3c0 R14: 00000000a1dab7e8 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff888124713000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc0819b7bac CR3: 000000005999c000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5871 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
uart_port_ref_lock drivers/tty/serial/serial_core.c:83 [inline]
uart_write+0x13b/0xb30 drivers/tty/serial/serial_core.c:627
handle_tx+0x201/0x630 drivers/net/caif/caif_serial.c:222
__netdev_start_xmit include/linux/netdevice.h:5215 [inline]
netdev_start_xmit include/linux/netdevice.h:5224 [inline]
xmit_one net/core/dev.c:3830 [inline]
dev_hard_start_xmit+0x94/0x740 net/core/dev.c:3846
__dev_queue_xmit+0x7eb/0x43e0 net/core/dev.c:4713
dev_queue_xmit include/linux/netdevice.h:3355 [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:464
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245