rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12097/1:b..l P12096/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=44009, q=1407 ncpus=2)
task:syz.0.1636 state:R running task stack:26440 pid:12096 tgid:12093 ppid:5812 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
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]
do_wp_page+0xf5c/0x5010 mm/memory.c:4175
handle_pte_fault mm/memory.c:6289 [inline]
__handle_mm_fault+0x1bd2/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
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 e9 d7 c0 03 00 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 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9001b6779e8 EFLAGS: 00050246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000020000025e030
RDX: 0000000000080000 RSI: ffffffff893bcde3 RDI: 0000000000000005
RBP: ffffc9001b677d88 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: 000020000025e000 R14: ffffc9001b677dcc R15: 0000000000000002
____sys_recvmsg+0x2ee/0x6b0 net/socket.c:2825
___sys_recvmsg+0x114/0x1a0 net/socket.c:2854
do_recvmmsg+0x2fe/0x750 net/socket.c:2949
__sys_recvmmsg net/socket.c:3023 [inline]
__do_sys_recvmmsg net/socket.c:3046 [inline]
__se_sys_recvmmsg net/socket.c:3039 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd39418f749
RSP: 002b:00007fd394f8c038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fd3943e6090 RCX: 00007fd39418f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fd394213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd3943e6128 R14: 00007fd3943e6090 R15: 00007ffcdb11c8c8
task:syz.2.1634 state:R running task stack:26440 pid:12097 tgid:12089 ppid:5813 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x14c2/0x20b0 arch/x86/kernel/unwind_orc.c:663
Code: df 48 8d 79 02 48 89 f8 48 c1 e8 03 0f b6 34 10 48 8d 41 03 49 89 c0 49 c1 e8 03 41 0f b6 14 10 49 89 f8 41 83 e0 07 44 38 c6 <41> 0f 9e c0 40 84 f6 40 0f 95 c6 41 84 f0 0f 85 b6 08 00 00 83 e0
RSP: 0018:ffffc9001bdc6cf8 EFLAGS: 00000246
RAX: ffffffff912ecc59 RBX: 0000000000000001 RCX: ffffffff912ecc56
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff912ecc58
RBP: ffffc9001bdc6db0 R08: 0000000000000000 R09: 00000000fb19a5cc
R10: 0000000000000002 R11: 0000000000011b0a R12: ffffc9001bdc6db8
R13: ffffc9001bdc6d68 R14: ffffc9001bdc7418 R15: ffffc9001bdc6d9c
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:165
__set_page_owner+0x91/0x560 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1884
prep_new_page mm/page_alloc.c:1892 [inline]
get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3945
__alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5240
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1890
shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1932
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_fault+0x1fe/0xa00 mm/shmem.c:2757
__do_fault+0x10d/0x490 mm/memory.c:5320
do_read_fault mm/memory.c:5755 [inline]
do_fault+0xae4/0x1ad0 mm/memory.c:5889
do_pte_missing mm/memory.c:4401 [inline]
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x54e/0x3590 mm/gup.c:1428
populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860
__mm_populate+0x1d8/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3701 [inline]
vm_mmap_pgoff+0x37f/0x470 mm/util.c:586
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f795f98f749
RSP: 002b:00007f796081c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f795fbe6090 RCX: 00007f795f98f749
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f795fa13f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f795fbe6128 R14: 00007f795fbe6090 R15: 00007ffcebe1bde8
rcu: rcu_preempt kthread starved for 9523 jiffies! g44009 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28064 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
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+0x983/0xb10 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: 1 UID: 0 PID: 0 Comm: swapper/1 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 26 5f 02 c3 cc cc cc cc 0f 1f 00 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 13 99 11 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6
RAX: 0000000002b9ca65 RBX: 0000000000000001 RCX: ffffffff8b78c6d9
RDX: 0000000000000000 RSI: ffffffff8dacf709 RDI: ffffffff8bf2b580
RBP: ffffed1003b59498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dacaff0 R12: 0000000000000001
R13: ffff88801daca4c0 R14: ffffffff9088cdd0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881249f1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe045843f8a CR3: 000000001fa91000 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+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148