rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P20822/1:b..l P20762/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=122181, q=386 ncpus=2)
task:syz.2.3333 state:R running task stack:24520 pid:20762 ppid:18654 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867
preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1523 [inline]
zap_pmd_range mm/memory.c:1571 [inline]
zap_pud_range mm/memory.c:1600 [inline]
zap_p4d_range mm/memory.c:1621 [inline]
unmap_page_range+0x2315/0x3000 mm/memory.c:1642
unmap_vmas+0x286/0x3f0 mm/memory.c:1732
exit_mmap+0x238/0xb90 mm/mmap.c:3302
__mmput+0x118/0x3c0 kernel/fork.c:1355
exit_mm+0x1f2/0x2c0 kernel/exit.c:569
do_exit+0x8dd/0x2460 kernel/exit.c:870
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
get_signal+0x12fc/0x13f0 kernel/signal.c:2902
arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f94c9b9d8ca
RSP: 002b:00007f94ca9fae58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: 0000000000000000 RBX: 00007f94ca9faee0 RCX: 00007f94c9b9d8ca
RDX: 0000200000000180 RSI: 0000200000009640 RDI: 00007f94ca9faea0
RBP: 0000200000000180 R08: 00007f94ca9faee0 R09: 0000000000000094
R10: 0000000000000094 R11: 0000000000000246 R12: 0000200000009640
R13: 00007f94ca9faea0 R14: 00000000000097cd R15: 00002000000000c0
task:rm state:R running task stack:24232 pid:20822 ppid:20786 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__sanitizer_cov_trace_switch+0x107/0x120 kernel/kcov.c:351
Code: 63 28 4d 39 fc 77 9d 49 ff c6 4d 89 33 49 89 4c 1b 08 4d 89 54 1b 10 49 89 7c 1b 18 49 89 54 1b 20 eb 81 5b 41 5c 41 5e 41 5f b9 05 00 00 00 48 85 c0 0f 85 52 ff ff ff c3 66 0f 1f 84 00 00
RSP: 0018:ffffc9000431f708 EFLAGS: 00000246
RAX: 0000000000000003 RBX: ffffc9000431f838 RCX: 0000000000000005
RDX: ffffffff8a720d27 RSI: ffffffff8e72cab0 RDI: 0000000000000003
RBP: ffffc9000431f930 R08: ffff88802c041e00 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000003
R13: 0000000000000002 R14: ffffc9000431f820 R15: dffffc0000000000
ma_pivots lib/maple_tree.c:651 [inline]
mas_descend+0x67/0x450 lib/maple_tree.c:1043
mt_validate_nulls lib/maple_tree.c:7179 [inline]
mt_validate+0x3ca2/0x4400 lib/maple_tree.c:7237
validate_mm+0xc6/0x450 mm/mmap.c:288
mmap_region+0xe8d/0x2000 mm/mmap.c:2947
do_mmap+0x92c/0x10a0 mm/mmap.c:1385
vm_mmap_pgoff+0x1c4/0x3f0 mm/util.c:556
ksys_mmap_pgoff+0x520/0x700 mm/mmap.c:1431
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff58ec30242
RSP: 002b:00007ffd4f9a49e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ff58e919000 RCX: 00007ff58ec30242
RDX: 0000000000000005 RSI: 000000000001c000 RDI: 00007ff58e919000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000008000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffd4f9a4a38
R13: 00007ff58ec0dab0 R14: 00007ffd4f9a4e60 R15: 00000fffa9f34940
rcu: rcu_preempt kthread starved for 10248 jiffies! g122181 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:27656 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: c7 22 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 83 d1 43 00 fb f4 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffffff8ce07d80 EFLAGS: 000002c2
RAX: 3e66809b518cf000 RBX: ffffffff8162a490 RCX: 3e66809b518cf000
RDX: 0000000000000001 RSI: ffffffff8acac900 RDI: ffffffff8b1c82e0
RBP: ffffffff8ce07eb8 R08: ffff8880b8e36b2b R09: 1ffff110171c6d65
R10: dffffc0000000000 R11: ffffed10171c6d66 R12: 1ffffffff19d2688
R13: 1ffffffff19c0fbc R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005611be75ca38 CR3: 0000000024ee9000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1f0/0x4e0 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
rest_init+0x2e2/0x300 init/main.c:744
arch_call_rest_init+0xe/0x10 init/main.c:841
start_kernel+0x459/0x4e0 init/main.c:1086
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b