rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=80bc/1/0x4000000000000000 softirq=147263/147263 fqs=2
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P22718/1:b..l P22709/1:b..l P22734/1:b..l P22732/3:b..l
rcu: (detected by 1, t=10502 jiffies, g=154725, q=478 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22715 Comm: syz.5.4557 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:num_possible_cpus include/linux/cpumask.h:1222 [inline]
RIP: 0010:mm_get_cid kernel/sched/sched.h:3853 [inline]
RIP: 0010:sched_mm_cid_fork+0x5ba/0x1120 kernel/sched/core.c:10679
Code: 00 49 c7 c4 98 3e 1b 8e 49 c1 ec 03 41 bd 00 00 00 80 eb 0a 89 e8 f7 d8 0f 81 e3 fe ff ff f3 90 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 75 40 44 8b 35 3e 5c 86 0c 48 89 df 4c 89 f6
RSP: 0000:ffffc90003947c48 EFLAGS: 00000887
RAX: dffffc0000000000 RBX: ffff88807f24f9d0 RCX: 0000000080000001
RDX: dffffc0000000000 RSI: 0000000000000002 RDI: ffff88807f24f9d0
RBP: 0000000080000000 R08: 1ffff1100fe49de9 R09: 0000000000000000
R10: ffff88807f24f094 R11: fffff52000728f78 R12: 1ffffffff1c367d3
R13: 0000000080000000 R14: 0000000000000002 R15: ffff88807f24ee40
FS: 0000000000000000(0000) GS:ffff888125457000(0063) knlGS:00000000f5476b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000031e0cff8 CR3: 00000000366f4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
bprm_execve+0xda1/0x1460 fs/exec.c:1771
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_compat_sys_execveat fs/exec.c:1968 [inline]
__se_compat_sys_execveat fs/exec.c:1961 [inline]
__ia32_compat_sys_execveat+0xcd/0xf0 fs/exec.c:1961
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
do_int80_emulation+0x173/0x4d0 arch/x86/entry/syscall_32.c:172
asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:621
RIP: 0023:0xf7fb5f6c
Code: 90 85 d2 74 0a 89 ce 81 e6 ff 0f 00 00 89 32 85 c0 74 05 c1 e9 0c 89 08 31 c0 5e 5d c3 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 58 b8
RSP: 002b:00000000f547650c EFLAGS: 00000206 ORIG_RAX: 0000000000000166
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000001000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
task:modprobe state:R running task stack:23904 pid:22732 tgid:22732 ppid:84 task_flags:0x400000 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:389 [inline]
filemap_map_pages+0x1952/0x2050 mm/filemap.c:3936
do_fault_around mm/memory.c:5757 [inline]
do_read_fault mm/memory.c:5790 [inline]
do_fault mm/memory.c:5933 [inline]
do_pte_missing+0x211a/0x3490 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0x1bec/0x3310 mm/memory.c:6624
do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f675adcb9c0
RSP: 002b:00007ffe85207098 EFLAGS: 00010246
RAX: 00007f675adcb9c0 RBX: 00007f675ad51f18 RCX: 00007f675afcd5f0
RDX: 00007f675ad34580 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe852071c0 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f675ad34580 R11: 00007f675ad2b000 R12: 00007f675afcd5f0
R13: 00007f675ad522d8 R14: 00007f675aefbd58 R15: 00007f675ad2b000
task:modprobe state:R running task stack:23328 pid:22734 tgid:22734 ppid:18151 task_flags:0x40000c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:389 [inline]
zap_pte_range mm/memory.c:1959 [inline]
zap_pmd_range mm/memory.c:2021 [inline]
zap_pud_range mm/memory.c:2049 [inline]
zap_p4d_range mm/memory.c:2070 [inline]
unmap_page_range+0x3b71/0x48f0 mm/memory.c:2091
unmap_single_vma mm/memory.c:2133 [inline]
unmap_vmas+0x48f/0x6a0 mm/memory.c:2171
exit_mmap+0x280/0xa10 mm/mmap.c:1302
__mmput+0x118/0x430 kernel/fork.c:1175
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x6a2/0x23c0 kernel/exit.c:964
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
__do_sys_exit_group kernel/exit.c:1129 [inline]
__se_sys_exit_group kernel/exit.c:1127 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1127
x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f01e0cd06c5
RSP: 002b:00007ffefb75c928 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f01e0dd1fe8 RCX: 00007f01e0cd06c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001
RBP: 0000000000000001 R08: 00007ffefb75c8b8 R09: 0000000000000000
R10: 00007ffefb75c750 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f01e0dd0680 R15: 00007f01e0dd2000
task:syz.2.4555 state:R running task stack:25544 pid:22709 tgid:22702 ppid:18834 task_flags:0x400040 flags:0x08080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:114 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x75/0x2c0 mm/kasan/generic.c:200
Code: 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df 4f 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 <4d> 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c
RSP: 0000:ffffc90005e26a20 EFLAGS: 00000a07
RAX: ffffc90005e27701 RBX: dffffc0000000001 RCX: ffffffff81768c9e
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90005e26b98
RBP: 0000000000000000 R08: ffffc90005e26ba7 R09: 1ffff92000bc4d74
R10: dffffc0000000000 R11: fffff52000bc4d73 R12: ffffc90005e26b98
R13: 1ffff92000bc4d6b R14: fffff52000bc4d75 R15: 1ffff92000bc4d73
__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
unwind_next_frame+0xeae/0x23c0 arch/x86/kernel/unwind_orc.c:607
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 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+0x231/0x280 mm/page_alloc.c:1889
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2490
folio_alloc_mpol_noprof mm/mempolicy.c:2509 [inline]
vma_alloc_folio_noprof+0xea/0x210 mm/mempolicy.c:2544
folio_prealloc mm/memory.c:-1 [inline]
wp_page_copy mm/memory.c:3780 [inline]
do_wp_page+0x1204/0x5a00 mm/memory.c:4241
handle_pte_fault mm/memory.c:6333 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0x1520/0x3310 mm/memory.c:6624
do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1385
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
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 51 75 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90005e27858 EFLAGS: 00050282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000008015f018
RDX: ffff888041383d00 RSI: 0000000080000002 RDI: 00000000ffffffff
RBP: ffffc90005e279d0 R08: ffffc90005e27627 R09: 1ffff92000bc4ec4
R10: dffffc0000000000 R11: fffff52000bc4ec5 R12: 1ffff92000bc4f18
R13: 0000000080000002 R14: 000000008015f000 R15: dffffc0000000000
____sys_recvmsg+0x2be/0x4a0 net/socket.c:2825
___sys_recvmsg+0x215/0x590 net/socket.c:2854
do_recvmmsg+0x3a5/0x800 net/socket.c:2941
__sys_recvmmsg+0x1a5/0x290 net/socket.c:3023
__do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
__se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
__ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x20d/0x640 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f77f6c
RSP: 002b:00000000f541550c EFLAGS: 00000206 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
task:syz.2.4555 state:R running task stack:22528 pid:22718 tgid:22702 ppid:18834 task_flags:0x400140 flags:0x08080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x0/0x23c0 arch/x86/kernel/unwind_orc.c:485
Code: 0a cc 89 d9 80 e1 07 80 c1 03 38 c1 7c 92 48 89 df e8 e4 83 b9 00 eb 88 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 81 ec 98 00 00 00 49
RSP: 0018:ffffc90003876d40 EFLAGS: 00000287
RAX: ffffc90003876e30 RBX: ffffc90003876da8 RCX: 0000000000000001
RDX: ffffc90003876e38 RSI: dffffc0000000000 RDI: ffffc90003876da8
RBP: 1ffff9200070edb6 R08: ffffc90003876e01 R09: 0000000000000000
R10: ffffc90003876da8 R11: fffff5200070edc1 R12: ffffc90003876de0
R13: ffffc90003876db8 R14: 1ffff9200070edb7 R15: ffffc90003876db0
__unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5380
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
ref_tracker_alloc+0x15a/0x4c0 lib/ref_tracker.c:270
__netdev_tracker_alloc include/linux/netdevice.h:4436 [inline]
netdev_hold include/linux/netdevice.h:4465 [inline]
dst_init+0xd9/0x480 net/core/dst.c:52
dst_alloc+0x12a/0x170 net/core/dst.c:94
rt_dst_alloc net/ipv4/route.c:1651 [inline]
__mkroute_output net/ipv4/route.c:2655 [inline]
ip_route_output_key_hash_rcu+0x14d0/0x25d0 net/ipv4/route.c:2875
ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2705
__ip_route_output_key include/net/route.h:169 [inline]
ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2932
udp_sendmsg+0x154a/0x22f0 net/ipv4/udp.c:1451
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0x80a/0x9f0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
__sys_sendmmsg+0x2e7/0x4e0 net/socket.c:2728
__compat_sys_sendmmsg net/compat.c:360 [inline]
__do_compat_sys_sendmmsg net/compat.c:367 [inline]
__se_compat_sys_sendmmsg net/compat.c:364 [inline]
__ia32_compat_sys_sendmmsg+0xa2/0xc0 net/compat.c:364
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x20d/0x640 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f77f6c
RSP: 002b:00000000f4fd150c EFLAGS: 00000206 ORIG_RAX: 0000000000000159
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000080007fc0
RDX: 000000000800001d RSI: 000000000000001c RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10498 jiffies! g154725 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:28120 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 1 UID: 0 PID: 48 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x17/0x70 kernel/kcov.c:217
Code: cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 28 db 56 11 65 8b 15 49 db 56 11 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 a4 16 00 00
RSP: 0000:ffffc90000b876f8 EFLAGS: 00000202
RAX: ffffffff81b9cd6d RBX: 1ffff110170c8525 RCX: ffff888020a93d00
RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000b87840 R08: ffffffff9011ceb7 R09: 1ffffffff20239d6
R10: dffffc0000000000 R11: fffffbfff20239d7 R12: ffff8880b8642928
R13: dffffc0000000000 R14: ffff8880b873c000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125557000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000800bf018 CR3: 000000000e54c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
csd_lock_wait kernel/smp.c:342 [inline]
smp_call_function_many_cond+0xcfd/0x12c0 kernel/smp.c:877
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2761 [inline]
smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2971
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:900
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245