rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P19755/1:b..l P5195/1:b..l P19761/1:b..l P18728/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=120273, q=343 ncpus=2)
task:syz-executor state:R running task stack:21592 pid:18728 tgid:18728 ppid:18725 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7078
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:392 [inline]
copy_pte_range mm/memory.c:1331 [inline]
copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1581
copy_process+0x1812/0x3ba0 kernel/fork.c:2218
kernel_clone+0x21e/0x820 kernel/fork.c:2648
__do_sys_clone kernel/fork.c:2789 [inline]
__se_sys_clone kernel/fork.c:2773 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2773
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff4a6385e93
RSP: 002b:00007fff10eb5838 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff4a6385e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555676927d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000018e8de R15: 00007fff10eb59d0
task:syz.3.3261 state:R running task stack:26296 pid:19761 tgid:19757 ppid:18366 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313
Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 60 a1 92 65 8b 0d 08 a0
RSP: 0018:ffffc9000e1bf9d8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff88807e50dac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000e1bfad0 R08: ffff88807ac80603 R09: 1ffff1100f5900c0
R10: dffffc0000000000 R11: ffffed100f5900c1 R12: dffffc0000000000
R13: 0000000000210008 R14: 00002000000d9000 R15: 0000000000000000
rcu_read_unlock include/linux/rcupdate.h:879 [inline]
pte_unmap include/linux/pgtable.h:136 [inline]
follow_page_pte+0x1f0/0x13e0 mm/gup.c:892
follow_pmd_mask mm/gup.c:-1 [inline]
follow_pud_mask mm/gup.c:967 [inline]
follow_p4d_mask mm/gup.c:984 [inline]
follow_page_mask mm/gup.c:1023 [inline]
__get_user_pages+0xa6c/0x29f0 mm/gup.c:1426
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860
__mm_populate+0x24c/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3679 [inline]
vm_mmap_pgoff+0x387/0x4d0 mm/util.c:586
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f23bb78f749
RSP: 002b:00007f23b99d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f23bb9e6090 RCX: 00007f23bb78f749
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f23bb813f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f23bb9e6128 R14: 00007f23bb9e6090 R15: 00007ffeb3022a58
task:udevd state:R running task stack:23288 pid:5195 tgid:5195 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5945
Code: 18 00 00 b8 ff ff ff ff 65 0f c1 05 a3 b0 44 07 83 f8 01 75 25 9c 58 a9 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 90 0f 0b 90 48 c7
RSP: 0018:ffffc90002ea7948 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000046
RDX: ffff88807f470000 RSI: ffffffff8db82ed3 RDI: ffffffff8be085e0
RBP: 00000000ffffffff R08: ffffffff8263f8ec R09: ffffffff8e13efa0
R10: dffffc0000000000 R11: ffffed10039de025 R12: 0000000000000246
R13: ffff88807f470000 R14: ffffffff8e13efa0 R15: 0000000000000001
kernfs_root+0xf6/0x230 fs/kernfs/kernfs-internal.h:76
kernfs_active fs/kernfs/dir.c:39 [inline]
kernfs_dop_revalidate+0xd5/0x5e0 fs/kernfs/dir.c:1188
d_revalidate fs/namei.c:969 [inline]
lookup_fast+0x253/0x5b0 fs/namei.c:-1
walk_component fs/namei.c:2217 [inline]
link_path_walk+0x720/0x18d0 fs/namei.c:2589
path_lookupat+0xe4/0x8c0 fs/namei.c:2745
filename_lookup+0x212/0x570 fs/namei.c:2775
do_readlinkat+0xd9/0x500 fs/stat.c:576
__do_sys_readlink fs/stat.c:613 [inline]
__se_sys_readlink fs/stat.c:610 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:610
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe0a7c413a7
RSP: 002b:00007ffc59f685a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffc59f68a80 RCX: 00007fe0a7c413a7
RDX: 0000000000000400 RSI: 00007ffc59f685b0 RDI: 00007ffc59f68a80
RBP: 00007ffc59f685b0 R08: 0000556680474d54 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400
R13: 00000000000000fe R14: 0000556674d44be0 R15: 00007ffc59f69580
task:syz.4.3259 state:R running task stack:22272 pid:19755 tgid:19755 ppid:18728 task_flags:0x400640 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 60 fb be 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 7a 69 03 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 97 94 07
RSP: 0018:ffffc9000e15e200 EFLAGS: 00000286
RAX: e45aea3a73aeb100 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000007f360bd7 RSI: ffffffff8db82ed3 RDI: ffffffff8be085e0
RBP: ffffffff823179ea R08: ffffffff823179ea R09: ffffffff8e13efa0
R10: ffff888044be2718 R11: ffffffff81acb3b0 R12: 0000000000000002
R13: ffffffff8e13efa0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
__update_page_owner_handle+0x77/0x570 mm/page_owner.c:255
__set_page_owner+0x10b/0x4c0 mm/page_owner.c:342
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x23d/0x2a0 mm/page_alloc.c:1887
prep_new_page mm/page_alloc.c:1895 [inline]
get_page_from_freelist+0x23a5/0x2440 mm/page_alloc.c:3955
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5264
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505
shmem_alloc_folio mm/shmem.c:1902 [inline]
shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1944
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2539
shmem_get_folio mm/shmem.c:2645 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3298
generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3473
__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+0x1121/0x18b0 fs/coredump.c:1049
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200
get_signal+0x1108/0x1340 kernel/signal.c:3019
arch_do_signal_or_restart+0x9a/0x7a0 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+0x178/0x670 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7ff4a638f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007ff4a65e6090 RCX: 00007ff4a638f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007ff4a6413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ff4a65e6128 R14: 00007ff4a65e6090 R15: 00007fff10eb55b8
rcu: rcu_preempt kthread starved for 10293 jiffies! g120273 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:27488 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 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:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 43 5e 2b 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 0000000002ac99e1 RBX: ffffffff8197171e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d99f7ca RDI: ffffffff8be085e0
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa24670
R13: 1ffffffff1bd29b8 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c0a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30d07ff8 CR3: 0000000035240000 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+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x386/0x3d0 init/main.c:1207
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