rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=f70c/1/0x4000000000000000 softirq=15410/15411 fqs=114
rcu: (detected by 0, t=10502 jiffies, g=13921, q=149 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6012 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 c3 9b 11 65 8b 15 49 c3 9b 11 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 94 16 00 00
RSP: 0018:ffffc90003797c28 EFLAGS: 00000002
RAX: ffffffff84f4c982 RBX: 0000000000000001 RCX: ffff88802de9db80
RDX: 0000000080000001 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff88802de9f178 R08: 1ffff1100f5811b9 R09: 0000000000000000
R10: ffff88807ac08f0c R11: fffff520006f2f80 R12: dffffc0000000000
R13: 1ffffffff1c9cfd7 R14: 0000000080000000 R15: 0000000000000002
FS: 00007f76cb2966c0(0000) GS:ffff888124ef6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76ca3e9e80 CR3: 000000007ae9e000 CR4: 00000000003526f0
Call Trace:
percpu_counter_tree_items_size+0x22/0x80 lib/percpu_counter_tree.c:669
get_rss_stat_items_size include/linux/mm_types.h:1440 [inline]
mm_cpus_allowed include/linux/mm_types.h:1549 [inline]
mm_cidmask include/linux/mm_types.h:1558 [inline]
__mm_get_cid kernel/sched/sched.h:3826 [inline]
mm_get_cid+0xd6/0x160 kernel/sched/sched.h:3841
sched_mm_cid_fork+0x218/0x910 kernel/sched/core.c:10759
bprm_execve+0xdad/0x1470 fs/exec.c:1771
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_sys_execveat fs/exec.c:1941 [inline]
__se_sys_execveat fs/exec.c:1934 [inline]
__x64_sys_execveat+0xc7/0xf0 fs/exec.c:1934
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: 0033:0x7f76ca39c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f76cb296028 EFLAGS: 00000246 ORIG_RAX: 0000000000000142
RAX: ffffffffffffffda RBX: 00007f76ca615fa0 RCX: 00007f76ca39c799
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007f76ca432bd9 R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76ca616038 R14: 00007f76ca615fa0 R15: 00007ffeaa9c2c88
rcu: rcu_preempt kthread starved for 10274 jiffies! g13921 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:28008 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5349 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7044 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7059
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: 0 UID: 0 PID: 5943 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xce5/0x12c0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 f4 ff 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 9f fb 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 83 fb
RSP: 0000:ffffc90003b77840 EFLAGS: 00000293
RAX: ffffffff81bae14d RBX: 1ffff110170a8141 RCX: ffff8880271f0000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003b77970 R08: ffffffff905428f7 R09: 1ffffffff20a851e
R10: dffffc0000000000 R11: fffffbfff20a851f R12: ffff8880b8540a08
R13: dffffc0000000000 R14: ffff8880b843c000 R15: 0000000000000001
FS: 000055556f891500(0000) GS:ffff888124df6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556f8aca28 CR3: 000000002171a000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5d7/0x10e0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:345 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:103
wp_page_copy mm/memory.c:3840 [inline]
do_wp_page+0x3d58/0x4c10 mm/memory.c:4235
handle_pte_fault mm/memory.c:6321 [inline]
__handle_mm_fault mm/memory.c:6443 [inline]
handle_mm_fault+0x151d/0x3170 mm/memory.c:6612
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: 0033:0x7f76ca361320
Code: ab 28 00 48 8d 0c 1e 49 39 d0 49 89 48 60 0f 95 c2 48 29 d8 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 56 08 <48> 89 41 08 48 8d 4e 10 eb b0 48 8d 0d ff de 0c 00 ba 9e 10 00 00
RSP: 002b:00007ffeaa9c2e90 EFLAGS: 00010206
RAX: 00000000000065e1 RBX: 0000000000008040 RCX: 000055556f8aca20
RDX: 0000000000008041 RSI: 000055556f8a49e0 RDI: 0000000000000004
RBP: 0000000000000802 R08: 00007f76ca5ebe20 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000008030
R13: 0000000000000000 R14: 00007f76ca5ebe80 R15: 0000000000000000