rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6019/1:b..l P5769/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=12941, q=542 ncpus=2)
task:syz-executor state:R running task stack:21736 pid:5769 ppid:5764 flags:0x00004002
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:__reset_page_owner+0x6b/0x190 mm/page_owner.c:-1
Code: fc ff df bf 00 28 00 00 e8 42 01 00 00 89 44 24 04 0f b7 dd bf 20 00 00 00 89 de e8 9f 95 9e ff b8 01 00 00 00 48 89 5c 24 08 <89> d9 d3 e0 45 31 f6 85 c0 44 0f 4f f0 48 c7 c3 80 49 33 97 48 c1
RSP: 0018:ffffc9000450f660 EFLAGS: 00000293
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888029561e00 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: 00000000d5cdcd41 R09: 00000000f24b120b
R10: dffffc0000000000 R11: fffffbfff1d16056 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88801a48ca90
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1181 [inline]
free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365
free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504
release_pages+0x1f7a/0x2200 mm/swap.c:1022
__folio_batch_release+0x71/0xe0 mm/swap.c:1042
folio_batch_release include/linux/pagevec.h:83 [inline]
shmem_undo_range+0x630/0x1b20 mm/shmem.c:1026
shmem_truncate_range mm/shmem.c:1135 [inline]
shmem_evict_inode+0x245/0x9e0 mm/shmem.c:1264
evict+0x4ca/0x8d0 fs/inode.c:705
do_unlinkat+0x38c/0x590 fs/namei.c:4406
__do_sys_unlink fs/namei.c:4447 [inline]
__se_sys_unlink fs/namei.c:4445 [inline]
__x64_sys_unlink+0x49/0x50 fs/namei.c:4445
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: 0033:0x7f7c6fd9b887
RSP: 002b:00007fff18805858 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7c6fd9b887
RDX: 00007fff18805880 RSI: 00007fff18805910 RDI: 00007fff18805910
RBP: 00007fff18805910 R08: 00007fff18806910 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fff188069a0
R13: 00007f7c6fe32050 R14: 000000000001fde2 R15: 00007fff188069e0
task:syz.1.52 state:R running task stack:22856 pid:6019 ppid:5769 flags:0x00004002
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:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90004dee820 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: c9b5040b4b442f00
RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c89a0
RBP: ffffc90004dee928 R08: dffffc0000000000 R09: 1ffffffff22386a0
R10: dffffc0000000000 R11: fffffbfff22386a1 R12: 1ffff920009bdd10
R13: ffffffff8d1320a0 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock include/linux/rcupdate.h:786 [inline]
page_ext_get+0x3e/0x2b0 mm/page_ext.c:508
__page_table_check_zero+0x138/0x4b0 mm/page_table_check.c:148
prep_new_page mm/page_alloc.c:1588 [inline]
get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220
__alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500
__folio_alloc+0x10/0x20 mm/page_alloc.c:4532
vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2240
shmem_alloc_folio+0x1a9/0x2a0 mm/shmem.c:1679
shmem_alloc_and_acct_folio+0x1e6/0x6d0 mm/shmem.c:1704
shmem_get_folio_gfp+0xcde/0x2aa0 mm/shmem.c:2041
shmem_get_folio mm/shmem.c:2164 [inline]
shmem_write_begin+0xf2/0x420 mm/shmem.c:2706
generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4031
shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883
__kernel_write_iter+0x28c/0x690 fs/read_write.c:517
dump_emit_page fs/coredump.c:957 [inline]
dump_user_range+0x420/0x860 fs/coredump.c:984
elf_core_dump+0x31d0/0x3770 fs/binfmt_elf.c:2184
do_coredump+0x17cc/0x24d0 fs/coredump.c:833
get_signal+0x1133/0x13f0 kernel/signal.c:2888
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
irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:315
exc_page_fault+0x8c/0x100 arch/x86/mm/fault.c:1519
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f7c6fc52777
RSP: 002b:00007f7c70cf1120 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f7c6fd9c799
RDX: 00007f7c70cf1140 RSI: 00007f7c70cf1270 RDI: 000000000000000b
RBP: 00007f7c6fe32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f7c70016038 R14: 00007f7c70015fa0 R15: 00007fff188065e8
rcu: rcu_preempt kthread starved for 10372 jiffies! g12941 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:26440 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:
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: 6f 21 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 23 39 42 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: 000002c6
RAX: 12dfe817d3793400 RBX: ffffffff8162a8c1 RCX: 12dfe817d3793400
RDX: 0000000000000001 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c89a0
RBP: ffffffff8ce07eb8 R08: ffff8880b8e36b2b R09: 1ffff110171c6d65
R10: dffffc0000000000 R11: ffffed10171c6d66 R12: 1ffffffff19c0fbc
R13: dffffc0000000000 R14: 1ffffffff19d2688 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9837505008 CR3: 0000000060788000 CR4: 00000000003506f0
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:178 [inline]
do_idle+0x221/0x590 kernel/sched/idle.c:302
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401
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