rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6868/1:b..l P5834/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=23597, q=424 ncpus=2)
task:syz-executor state:R running task stack:19496 pid:5834 tgid:5834 ppid:5819 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
RIP: 0010:unwind_next_frame+0x1948/0x23d0 arch/x86/kernel/unwind_orc.c:680
Code: 38 49 8d 7e 08 48 89 f8 48 c1 e8 03 80 3c 28 00 74 05 e8 2b a3 b3 00 4d 8b 6e 08 4d 8d 7e 10 4c 89 f8 48 c1 e8 03 80 3c 28 00 <74> 08 4c 89 ff e8 0e a3 b3 00 49 8b 07 4d 39 e5 0f 96 c1 4c 39 e0
RSP: 0018:ffffc9000411f2d8 EFLAGS: 00000246
RAX: 1ffff92000823e77 RBX: ffffffff90432b01 RCX: 0000000000000001
RDX: ffffc9000411f3e8 RSI: dffffc0000000000 RDI: ffffc9000411f3b0
RBP: dffffc0000000000 R08: ffffc9000411fa00 R09: 0000000000000000
R10: ffffc9000411f3f8 R11: fffff52000823e81 R12: ffffc9000411fa10
R13: ffffc90004118000 R14: ffffc9000411f3a8 R15: ffffc9000411f3b8
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:4969 [inline]
slab_alloc_node mm/slub.c:5283 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5290
anon_vma_chain_alloc mm/rmap.c:142 [inline]
anon_vma_fork+0x1f6/0x500 mm/rmap.c:408
dup_mmap+0x954/0x1b80 mm/mmap.c:1790
dup_mm kernel/fork.c:1533 [inline]
copy_mm+0x14f/0x770 kernel/fork.c:1585
copy_process+0x1812/0x3ba0 kernel/fork.c:2222
kernel_clone+0x21e/0x820 kernel/fork.c:2652
__do_sys_clone kernel/fork.c:2793 [inline]
__se_sys_clone kernel/fork.c:2777 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2777
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde29585e93
RSP: 002b:00007ffcebc81b68 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fde29585e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555586c517d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000038550 R15: 00007ffcebc81d00
task:syz.0.219 state:R running task stack:25096 pid:6868 tgid:6866 ppid:5824 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x15/0x3b0 kernel/locking/lockdep.c:5876
Code: ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 <49> 89 fe 65 48 8b 05 30 05 04 11 48 89 44 24 28 0f 1f 44 00 00 65
RSP: 0018:ffffc9001b6d6a30 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffffffff90bc9901 RCX: 0000000080000001
RDX: ffffc9001b6d6b01 RSI: ffffffff81745df5 RDI: ffffffff8e144f60
RBP: dffffc0000000000 R08: ffffc9001b6d7e10 R09: 0000000000000000
R10: ffffc9001b6d6bb8 R11: fffff520036dad79 R12: ffffc9001b6d7e20
R13: ffffffff81745df5 R14: ffffc9001b6d6b68 R15: ffffffff81745df5
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x23d/0x2a0 mm/page_alloc.c:1887
prep_new_page mm/page_alloc.c:1895 [inline]
get_page_from_freelist+0x23a5/0x2440 mm/page_alloc.c:3948
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5236
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
folio_alloc_mpol_noprof mm/mempolicy.c:2505 [inline]
vma_alloc_folio_noprof+0xe4/0x200 mm/mempolicy.c:2540
folio_prealloc+0x30/0x180 mm/memory.c:-1
wp_page_copy mm/memory.c:3719 [inline]
do_wp_page+0x1231/0x5760 mm/memory.c:4180
handle_pte_fault mm/memory.c:6271 [inline]
__handle_mm_fault mm/memory.c:6393 [inline]
handle_mm_fault+0x14c5/0x32b0 mm/memory.c:6562
do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x71/0xd0 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 90 90 90 90 90 90 90 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 6c 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9001b6d78b8 EFLAGS: 00050202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00002000003fe030
RDX: ffff88802b9f9e40 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc9001b6d7a30 R08: ffffc9001b6d7667 R09: 1ffff920036daecc
R10: dffffc0000000000 R11: fffff520036daecd R12: 0000000000000002
R13: 00002000003fe000 R14: 0000000000000000 R15: dffffc0000000000
____sys_recvmsg+0x2f5/0x4c0 net/socket.c:2843
___sys_recvmsg+0x1b5/0x510 net/socket.c:2872
do_recvmmsg+0x307/0x770 net/socket.c:2967
__sys_recvmmsg net/socket.c:3041 [inline]
__do_sys_recvmmsg net/socket.c:3064 [inline]
__se_sys_recvmmsg net/socket.c:3057 [inline]
__x64_sys_recvmmsg+0x190/0x240 net/socket.c:3057
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1333b8f749
RSP: 002b:00007f133495f038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f1333de6090 RCX: 00007f1333b8f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007f1333c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1333de6128 R14: 00007f1333de6090 R15: 00007ffcdcb33f48
rcu: rcu_preempt kthread starved for 10601 jiffies! g23597 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:27656 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 3f 29 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 00000000004fb755 RBX: ffffffff81977eae RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a99b4 RDI: ffffffff8be09d60
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa2d8f0
R13: 1ffffffff1bd29d0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125bf7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9deef5ed76 CR3: 000000007ae9a000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:758
start_kernel+0x38b/0x3e0 init/main.c:1209
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147