rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15803/1:b..l P15793/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=58129, q=248 ncpus=2)
task:syz.5.2352 state:R running task stack:24040 pid:15793 tgid:15793 ppid:6124 task_flags:0x400640 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_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: e3 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 e3 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc90004a6ee20 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 00000000747ed0a7
RDX: 0000000000000000 RSI: ffffffff8daa967a RDI: ffffffff8bf2b580
RBP: 0000000000000002 R08: 00000000f9a44957 R09: 000000007f9a4495
R10: 0000000000000002 R11: ffff88802f11aff0 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]
count_memcg_events_mm.constprop.0+0x40/0x2a0 include/linux/memcontrol.h:982
count_memcg_event_mm include/linux/memcontrol.h:992 [inline]
mm_account_fault mm/memory.c:6445 [inline]
handle_mm_fault+0x5f9/0xad0 mm/memory.c:6606
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x54e/0x3590 mm/gup.c:1428
__get_user_pages_locked mm/gup.c:1692 [inline]
get_dump_page+0x257/0x3d0 mm/gup.c:2192
dump_user_range+0x195/0xb70 fs/coredump.c:1366
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: 0033:0x7fa73864f6b7
RSP: 002b:00007fa7369d71a0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fa73878f749
RDX: 00007fa7369d71c0 RSI: 00007fa7369d72f0 RDI: 000000000000000b
RBP: 00007fa738813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fa7389e6128 R14: 00007fa7389e6090 R15: 00007ffe6e9e1638
task:syz-executor state:R running task stack:28888 pid:15803 tgid:15803 ppid:10166 task_flags:0x400040 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_release+0x183/0x2d0 kernel/locking/lockdep.c:5893
Code: 0f c1 05 28 30 19 12 83 f8 01 0f 85 03 01 00 00 9c 58 f6 c4 02 0f 85 ee 00 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 bd e8 18 12 0f 85 32 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc90004cef820 EFLAGS: 00000206
RAX: f16088c26bc86300 RBX: ffffffff8e3c96a0 RCX: ffffc90004cef82c
RDX: 0000000000000002 RSI: ffffffff8daa967a RDI: ffffffff8bf2b580
RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000cd186aa9
R10: 0000000000000002 R11: 0000000000014153 R12: ffffffff816cca34
R13: 0000000000000206 R14: ffff8880823ea4c0 R15: 0000000000000003
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x3f9/0x20b0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_node_track_caller_noprof+0x353/0x930 mm/slub.c:5764
kmemdup_noprof+0x29/0x60 mm/util.c:138
kmemdup_noprof include/linux/fortify-string.h:765 [inline]
shmem_symlink+0x256/0x960 mm/shmem.c:4119
vfs_symlink fs/namei.c:5523 [inline]
vfs_symlink+0x4b5/0x800 fs/namei.c:5502
do_symlinkat+0x353/0x4b0 fs/namei.c:5550
__do_sys_symlinkat fs/namei.c:5571 [inline]
__se_sys_symlinkat fs/namei.c:5568 [inline]
__x64_sys_symlinkat+0x93/0xc0 fs/namei.c:5568
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: 0033:0x7f7523b8ecc7
RSP: 002b:00007ffd807fa4b8 EFLAGS: 00000206 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7523b8ecc7
RDX: 00007f7523c158e4 RSI: 00000000ffffff9c RDI: 00007ffd807fa550
RBP: 00007ffd807fa4fc R08: 0000000000000013 R09: 00007ffd807fa207
R10: 0000000000000000 R11: 0000000000000206 R12: 00000000000000f4
R13: 00000000000927c0 R14: 00000000000ddddb R15: 00007ffd807fa550
rcu: rcu_preempt kthread starved for 10576 jiffies! g58129 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:28440 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 26 5f 02 c3 cc cc cc cc 0f 1f 00 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 13 99 11 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 00000000039678df RBX: 0000000000000000 RCX: ffffffff8b78c6d9
RDX: 0000000000000000 RSI: ffffffff8dacf709 RDI: ffffffff8bf2b580
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088cdd0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248f1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c409997 CR3: 00000000885c8000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148