rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9768/1:b..l rcu: (detected by 0, t=10502 jiffies, g=49269, q=136 ncpus=2) task:syz.0.923 state:R running task stack:23528 pid:9768 tgid:9767 ppid:5843 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7281 irqentry_exit+0x6f/0x90 kernel/entry/common.c:196 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x4e2/0x2390 arch/x86/kernel/unwind_orc.c:512 Code: 88 8b 4c 8b 6c 24 50 48 8d 72 04 4c 8d 62 05 48 89 f0 48 c1 e8 03 48 89 44 24 40 0f b6 04 28 84 c0 48 89 54 24 08 48 89 34 24 <0f> 85 4d 18 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 63 RSP: 0018:ffffc900025bed78 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8fb77464 RCX: ffffffff8fb77468 RDX: ffffffff9033f3b0 RSI: ffffffff9033f3b4 RDI: ffffffff8be34620 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8172b195 R10: ffffc900025bee98 R11: ffffffff81ac4660 R12: ffffffff9033f3b5 R13: ffffc900025bee98 R14: ffffc900025bee48 R15: ffffffff8172b195 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] free_unref_folios+0xdbd/0x1520 mm/page_alloc.c:2952 folios_put_refs+0x559/0x640 mm/swap.c:997 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1261 [inline] shmem_evict_inode+0x272/0xa70 mm/shmem.c:1389 evict+0x504/0x9c0 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:476 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:959 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f282d98d45f RSP: 002b:00007f282e888df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: 0000000000e9b000 RBX: 0000000001000000 RCX: 00007f282d98d45f RDX: 0000000001000000 RSI: 00007f2823200000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005a7f R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003 R13: 00007f282e888ef0 R14: 00007f282e888eb0 R15: 00007f2823200000 rcu: rcu_preempt kthread starved for 9411 jiffies! g49269 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:25800 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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 73 16 10 00 f3 0f 1e fa fb f4 c8 e8 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6 RAX: dc64912c1bf4a000 RBX: ffffffff81968a38 RCX: dc64912c1bf4a000 RDX: 0000000000000001 RSI: ffffffff8d992221 RDI: ffffffff8be34680 RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8fa2a730 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d5b40 FS: 0000000000000000(0000) GS:ffff888125ce3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f802f824d58 CR3: 00000000787fc000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147