rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21242/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=82101, q=261 ncpus=2)
task:syz.7.3278 state:R running task stack:26008 pid:21242 tgid:21240 ppid:11714 task_flags:0x400140 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:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: d3 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 52 c1 ee 0e 0f 82 74 02 00 00 8b 35 ea f1 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 69 d3 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000446ec30 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 0000000013d622c6
RDX: 0000000000000000 RSI: ffffffff8daa961b RDI: ffffffff8bf2b580
RBP: 0000000000000002 R08: 00000000accd7842 R09: 000000002accd784
R10: 0000000000000002 R11: ffff888056a154b0 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+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
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: 0033:0x7ffa9558f749
RSP: 002b:00007ffa9636f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ffa957e5fa0 RCX: 00007ffa9558f749
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007ffa95613f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffa957e6038 R14: 00007ffa957e5fa0 R15: 00007fff8e53a838
rcu: rcu_preempt kthread starved for 10398 jiffies! g82101 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:28192 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21249 Comm: syz.8.3279 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:match_held_lock+0xf/0xb0 kernel/locking/lockdep.c:5309
Code: 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 53 48 89 fb 48 39 77 10 74 55 66 83 7f 22 1f <76> 65 48 8b 46 08 48 89 f7 48 85 c0 74 4d 8b 15 1d cd 49 0f 85 d2
RSP: 0000:ffffc9000c6ee2f8 EFLAGS: 00000093
RAX: 0000000000000005 RBX: ffff8880323db018 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8e3c9640 RDI: ffff8880323db018
RBP: ffffffff8e3c9640 R08: 0000000009678e5e R09: 00000000e09678e5
R10: 0000000000000002 R11: ffff8880323daff0 R12: ffff8880323da4c0
R13: ffff8880323daff0 R14: 00000000ffffffff R15: 0000000000000001
FS: 00007fdff743e6c0(0000) GS:ffff8881248f2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdff67e0000 CR3: 0000000051a04000 CR4: 00000000003526f0
Call Trace:
__lock_is_held kernel/locking/lockdep.c:5601 [inline]
lock_is_held_type+0xb0/0x150 kernel/locking/lockdep.c:5940
lock_is_held include/linux/lockdep.h:249 [inline]
__might_resched+0x473/0x5e0 kernel/sched/core.c:8789
shrink_node_memcgs mm/vmscan.c:5993 [inline]
shrink_node+0x57b/0x3bb0 mm/vmscan.c:6061
shrink_zones mm/vmscan.c:6300 [inline]
do_try_to_free_pages+0x362/0x1920 mm/vmscan.c:6362
try_to_free_mem_cgroup_pages+0x31b/0x740 mm/vmscan.c:6690
try_charge_memcg+0x42a/0xd30 mm/memcontrol.c:2388
obj_cgroup_charge_pages mm/memcontrol.c:2823 [inline]
obj_cgroup_charge_account+0x336/0x670 mm/memcontrol.c:3126
__memcg_slab_post_alloc_hook+0x2e3/0x880 mm/memcontrol.c:3212
memcg_slab_post_alloc_hook mm/slub.c:2338 [inline]
slab_post_alloc_hook mm/slub.c:4964 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_lru_noprof+0x58f/0x770 mm/slub.c:5282
xas_nomem+0x101/0x2c0 lib/xarray.c:309
shmem_add_to_page_cache+0x6de/0xa70 mm/shmem.c:929
shmem_alloc_and_add_folio+0x662/0xc20 mm/shmem.c:1958
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_get_folio mm/shmem.c:2662 [inline]
shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
__kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x413/0xb70 fs/coredump.c:1372
elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
coredump_write fs/coredump.c:1049 [inline]
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
get_signal+0x22e1/0x26d0 kernel/signal.c:3019
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fdff644f6b0
Code: Unable to access opcode bytes at 0x7fdff644f686.
RSP: 002b:00007fdff741f1f8 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 00007fdff67e6360 RCX: 00007fdff658f749
RDX: 00007fdff741f200 RSI: 00007fdff741f330 RDI: 000000000000000b
RBP: 00007fdff6613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fdff67e63f8 R14: 00007fdff67e6360 R15: 00007ffd867c1c88