rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17477/1:b..l P11328/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=108769, q=598 ncpus=2)
task:syz-executor state:R running task stack:19496 pid:11328 tgid:11328 ppid:11323 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 44 41 01 11 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000b866d78 EFLAGS: 00000206
RAX: cca33b67e861eb00 RBX: 0000000000000000 RCX: cca33b67e861eb00
RDX: 00000000d5f66617 RSI: ffffffff8db7ed49 RDI: ffffffff8be07960
RBP: ffffffff81742f85 R08: ffffffff81742f85 R09: ffffffff8e13f2e0
R10: ffffc9000b866f38 R11: ffffffff81ad9d50 R12: 0000000000000002
R13: ffffffff8e13f2e0 R14: 0000000000000000 R15: 0000000000000246
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+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5267 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5274
ptlock_alloc+0x20/0x70 mm/memory.c:7377
ptlock_init include/linux/mm.h:3327 [inline]
pagetable_pte_ctor include/linux/mm.h:3381 [inline]
__pte_alloc_one_noprof include/asm-generic/pgalloc.h:79 [inline]
pte_alloc_one+0x7a/0x370 arch/x86/mm/pgtable.c:18
__pte_alloc+0x25/0x1a0 mm/memory.c:453
copy_pte_range mm/memory.c:1237 [inline]
copy_pmd_range+0x7931/0x8060 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1533 [inline]
copy_mm+0x14f/0x770 kernel/fork.c:1585
copy_process+0x165d/0x3950 kernel/fork.c:2225
kernel_clone+0x21e/0x820 kernel/fork.c:2655
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5dd5d85e93
RSP: 002b:00007ffeb11efc88 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5dd5d85e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055557e03d7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 000055557e050590 R14: 00000000000eb543 R15: 00007ffeb11efe20
task:syz-executor state:R running task stack:21592 pid:17477 tgid:17477 ppid:17471 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7050
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7074
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+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1331 [inline]
copy_pmd_range+0x7773/0x8060 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1533 [inline]
copy_mm+0x14f/0x770 kernel/fork.c:1585
copy_process+0x165d/0x3950 kernel/fork.c:2225
kernel_clone+0x21e/0x820 kernel/fork.c:2655
__do_sys_clone kernel/fork.c:2796 [inline]
__se_sys_clone kernel/fork.c:2780 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2780
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e28585e93
RSP: 002b:00007ffef6eec898 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3e28585e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055557bee77d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000eb9e3 R15: 00007ffef6eeca30
rcu: rcu_preempt kthread starved for 10580 jiffies! g108769 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:27424 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 17911 Comm: syz.0.2530 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:unix_stream_read_generic+0xabc/0x2390 net/unix/af_unix.c:3067
Code: 00 00 00 89 54 24 2c 48 89 8c 24 b0 00 00 00 0f 84 17 09 00 00 48 8b 44 24 20 4c 8d 70 38 4c 89 f0 48 c1 e8 03 48 89 44 24 30 <42> 80 3c 20 00 74 08 4c 89 f7 e8 55 e0 22 f8 4d 8b 3e 4d 85 ff 4c
RSP: 0018:ffffc900038e7680 EFLAGS: 00000a02
RAX: 1ffff11008ef8e2f RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900038e78d0 R08: ffffffff820fad90 R09: ffff888031514e40
R10: dffffc0000000000 R11: fffffbfff1f445ef R12: dffffc0000000000
R13: 1ffff11008ef8e36 R14: ffff8880477c7178 R15: 1ffff11008ef8e30
FS: 00007f1a80bcd6c0(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c45e11c CR3: 000000003221c000 CR4: 00000000003526f0
Call Trace:
unix_stream_recvmsg+0x15d/0x1b0 net/unix/af_unix.c:3146
sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1093
____sys_recvmsg+0x21e/0x4c0 net/socket.c:-1
___sys_recvmsg+0x1b5/0x510 net/socket.c:2872
__sys_recvmsg net/socket.c:2905 [inline]
__do_sys_recvmsg net/socket.c:2911 [inline]
__se_sys_recvmsg net/socket.c:2908 [inline]
__x64_sys_recvmsg+0x198/0x260 net/socket.c:2908
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a8298f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f1a80bcd038 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f1a82be6090 RCX: 00007f1a8298f749
RDX: 0000000000014006 RSI: 0000200000000600 RDI: 0000000000000005
RBP: 00007f1a82a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a82be6128 R14: 00007f1a82be6090 R15: 00007ffcc8cb85d8