rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8456/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=28737, q=600 ncpus=2)
task:syz.4.891 state:R running task stack:25096 pid:8456 tgid:8456 ppid:5851 task_flags:0x40004c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x11/0x70 kernel/kcov.c:217
Code: 5b e9 33 20 55 00 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 0c 25 08 90 9c 92 <65> 8b 15 58 6a dc 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0000:ffffc900030d72e0 EFLAGS: 00000206
RAX: ffffffff822b22cf RBX: 0000000000000000 RCX: ffff88802abbda00
RDX: 0000000000000000 RSI: 0000000000000717 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff88801d02372f R09: 1ffff11003a046e5
R10: dffffc0000000000 R11: ffffed1003a046e6 R12: ffff88801d0236e0
R13: 0000000000000000 R14: 0000000000050717 R15: 0000000000050717
page_ext_next include/linux/page_ext.h:108 [inline]
page_ext_iter_next include/linux/page_ext.h:156 [inline]
__page_table_check_zero+0x2af/0x530 mm/page_table_check.c:139
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1249 [inline]
free_unref_folios+0xce5/0x1570 mm/page_alloc.c:2763
folios_put_refs+0x559/0x640 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x501/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:473
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x22e0 kernel/exit.c:964
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
__do_sys_exit_group kernel/exit.c:1116 [inline]
__se_sys_exit_group kernel/exit.c:1114 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114
x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f38d658eb69
RSP: 002b:00007ffc1f00df28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f38d658eb69
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc1f00df8c R08: 000000071f00e01f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000c1
R13: 00000000000927c0 R14: 0000000000032769 R15: 00007ffc1f00dfe0
rcu: rcu_preempt kthread starved for 10495 jiffies! g28737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 8472 Comm: syz.5.894 Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 80 6e 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 2b 6a 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 10 6a 0b
RSP: 0018:ffffc900033a67e0 EFLAGS: 00000246
RAX: ffffffff81b4bbb0 RBX: ffff8880b873b040 RCX: 0000000000080000
RDX: ffffc90012f59000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900033a6940 R08: ffffffff8fa0b3f7 R09: 1ffffffff1f4167e
R10: dffffc0000000000 R11: fffffbfff1f4167f R12: 1ffff110170c835d
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8
FS: 00007f0d03f346c0(0000) GS:ffff888125d57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe46097f38 CR3: 0000000055dcc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000004144
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
arch_tlbbatch_flush+0x324/0x570 arch/x86/mm/tlb.c:1725
try_to_unmap_flush mm/rmap.c:650 [inline]
try_to_unmap_flush_dirty+0x75/0x100 mm/rmap.c:661
shrink_folio_list+0x2b8e/0x4d10 mm/vmscan.c:1459
reclaim_folio_list+0xee/0x500 mm/vmscan.c:2240
reclaim_pages+0x49a/0x5b0 mm/vmscan.c:2277
madvise_cold_or_pageout_pte_range+0x19da/0x1d60 mm/madvise.c:564
walk_pmd_range mm/pagewalk.c:130 [inline]
walk_pud_range mm/pagewalk.c:226 [inline]
walk_p4d_range mm/pagewalk.c:264 [inline]
walk_pgd_range+0x1096/0x1e70 mm/pagewalk.c:305
__walk_page_range+0x14c/0x710 mm/pagewalk.c:412
walk_page_range_mm+0x42d/0x620 mm/pagewalk.c:505
madvise_pageout_page_range mm/madvise.c:623 [inline]
madvise_pageout mm/madvise.c:650 [inline]
madvise_vma_behavior mm/madvise.c:1280 [inline]
madvise_walk_vmas mm/madvise.c:1541 [inline]
madvise_do_behavior+0x1c01/0x2e70 mm/madvise.c:1733
do_madvise+0x174/0x220 mm/madvise.c:1826
__do_sys_madvise mm/madvise.c:1835 [inline]
__se_sys_madvise mm/madvise.c:1833 [inline]
__x64_sys_madvise+0xa7/0xc0 mm/madvise.c:1833
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d0318eb69
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0d03f34038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f0d033b6080 RCX: 00007f0d0318eb69
RDX: 0000000000000015 RSI: 0000000000c00000 RDI: 0000200000000000
RBP: 00007f0d03211df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0d033b6080 R15: 00007ffc945f6d18