rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12992/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=69121, q=1380312 ncpus=2)
task:syz.6.1342 state:R running task stack:20992 pid:12992 tgid:12992 ppid:12007 task_flags:0x400640 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7206
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
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+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
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:156
__set_page_owner+0x8d/0x4a0 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
prep_new_page mm/page_alloc.c:1858 [inline]
get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2435
shmem_alloc_folio mm/shmem.c:1871 [inline]
shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1910
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2533
shmem_get_folio mm/shmem.c:2639 [inline]
shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3289
generic_perform_write+0x2c5/0x900 mm/filemap.c:4242
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3464
__kernel_write_iter+0x428/0x910 fs/read_write.c:619
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x8a0/0xc90 fs/coredump.c:1372
elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111
coredump_write+0x116c/0x1900 fs/coredump.c:1049
vfs_coredump+0x1db5/0x2a60 fs/coredump.c:1170
get_signal+0x1108/0x1340 kernel/signal.c:3019
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
irqentry_exit_to_user_mode+0x7e/0x110 kernel/entry/common.c:73
exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x0
RSP: 002b:00002000000002c8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f3f0dbe5fa0 RCX: 00007f3f0d98eec9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000001000000
RBP: 00007f3f0da11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f3f0dbe6038 R14: 00007f3f0dbe5fa0 R15: 00007fff5dc5c7c8
rcu: rcu_preempt kthread starved for 1409 jiffies! g69121 f0x2 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
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 10/02/2025
RIP: 0010:unwind_next_frame+0x1174/0x2390 arch/x86/kernel/unwind_orc.c:641
Code: 8b 14 24 4d 89 65 00 41 0f b6 04 2f 84 c0 0f 85 f9 0f 00 00 c6 03 00 4c 8b 64 24 10 4c 8b 7c 24 28 48 8b 44 24 40 0f b6 04 28 <84> c0 0f 85 8a 0d 00 00 41 0f b6 04 2f 84 c0 0f 85 a1 0d 00 00 0f
RSP: 0018:ffffc90000006618 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc90000006720 RCX: 0000000000000000
RDX: ffffffff90d48d8a RSI: 0000000000000000 RDI: ffffc90000006748
RBP: dffffc0000000000 R08: ffffc90000006747 R09: ffffc90000006738
R10: dffffc0000000000 R11: fffff52000000ce9 R12: ffffffff8de07f48
R13: ffffc90000006738 R14: ffffc900000066e8 R15: 1ffffffff21a91b1
FS: 0000000000000000(0000) GS:ffff888125d0c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd592fb77c CR3: 0000000061deb000 CR4: 0000000000350ef0
Call Trace:
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:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3d5/0x6f0 mm/slub.c:5748
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271
__netdev_tracker_alloc include/linux/netdevice.h:4375 [inline]
netdev_hold include/linux/netdevice.h:4404 [inline]
dst_init+0xd9/0x450 net/core/dst.c:52
dst_alloc+0x12a/0x170 net/core/dst.c:93
rt_dst_alloc net/ipv4/route.c:1646 [inline]
__mkroute_output net/ipv4/route.c:2650 [inline]
ip_route_output_key_hash_rcu+0x1560/0x23e0 net/ipv4/route.c:2870
ip_route_output_key_hash+0x174/0x280 net/ipv4/route.c:2700
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2927
ip_route_output_key include/net/route.h:179 [inline]
ip_route_me_harder+0x6c4/0xf10 net/ipv4/netfilter.c:53
synproxy_send_tcp+0x3a7/0x700 net/netfilter/nf_synproxy_core.c:431
synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6079 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6192
process_backlog+0x60e/0x14f0 net/core/dev.c:6544
__napi_poll+0xc7/0x360 net/core/dev.c:7594
napi_poll net/core/dev.c:7657 [inline]
net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
handle_softirqs+0x286/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 5e 33 c4 f5 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 33 21 1c 00 f3 0f 1e fa fb f4 33 33 c4 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c6
RAX: 327b33690d4b0c00 RBX: ffffffff8196bc07 RCX: 327b33690d4b0c00
RDX: 0000000000000001 RSI: ffffffff8d7e835a RDI: ffffffff8bc076e0
RBP: ffffffff8de07ea8 R08: ffff8880b8632fdb R09: 1ffff110170c65fb
R10: dffffc0000000000 R11: ffffed10170c65fc R12: ffffffff8f9e1170
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a40
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:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3ae/0x410 init/main.c:1111
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