rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5207/1:b..l rcu: (detected by 0, t=10502 jiffies, g=8669, q=1213 ncpus=2) task:syz.0.12 state:R running task stack:25840 pid:5207 tgid:5206 ppid:5082 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2c/0x6c0 kernel/locking/lockdep.c:5762 Code: 1e fa 48 b8 00 00 00 00 00 fc ff df 41 57 41 56 41 55 41 54 49 89 fc 55 53 48 81 ec 90 00 00 00 48 8d 6c 24 10 48 89 74 24 08 <48> c7 44 24 10 b3 8a b5 41 48 c1 ed 03 48 c7 44 24 18 88 32 26 8d RSP: 0018:ffffc9000345f430 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc90003602000 RDX: 0000000000040000 RSI: ffffffff81d1d23d RDI: ffffffff8dbb1620 RBP: ffffc9000345f440 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: ffffffff8dbb1620 R13: ffffc9000345f6e8 R14: ffff888011c25c98 R15: ffffc9000345f740 rcu_lock_release include/linux/rcupdate.h:339 [inline] rcu_read_unlock+0x32/0xb0 include/linux/rcupdate.h:812 pte_unmap include/linux/pgtable.h:115 [inline] wp_page_copy mm/memory.c:3386 [inline] do_wp_page+0x1559/0x3340 mm/memory.c:3677 handle_pte_fault mm/memory.c:5397 [inline] __handle_mm_fault+0x2311/0x5410 mm/memory.c:5524 handle_mm_fault+0x476/0xa00 mm/memory.c:5689 do_user_addr_fault+0x2e5/0xe50 arch/x86/mm/fault.c:1389 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1 RSP: 0018:ffffc9000345f958 EFLAGS: 00050206 RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000e80 RDX: 0000000000000000 RSI: ffff888012e75180 RDI: 0000000020620000 RBP: 0000000000001000 R08: 0000000000000000 R09: ffffed10025cebff R10: ffff888012e75fff R11: 0000000000000000 R12: 000000000061fb80 R13: ffffc9000345fd50 R14: ffff888012e75000 R15: 000000002061fe80 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_iovec include/linux/iov_iter.h:51 [inline] iterate_and_advance2 include/linux/iov_iter.h:247 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] _copy_to_iter+0x4d2/0x1140 lib/iov_iter.c:185 copy_page_to_iter lib/iov_iter.c:362 [inline] copy_page_to_iter+0xf1/0x180 lib/iov_iter.c:349 process_vm_rw_pages mm/process_vm_access.c:45 [inline] process_vm_rw_single_vec mm/process_vm_access.c:118 [inline] process_vm_rw_core.constprop.0+0x5c9/0xa10 mm/process_vm_access.c:216 process_vm_rw+0x301/0x360 mm/process_vm_access.c:284 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline] __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline] __x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7effbd175bd9 RSP: 002b:00007effbde89048 EFLAGS: 00000246 ORIG_RAX: 0000000000000136 RAX: ffffffffffffffda RBX: 00007effbd303f60 RCX: 00007effbd175bd9 RDX: 0000000000000002 RSI: 0000000020008400 RDI: 0000000000000008 RBP: 00007effbd1e4e60 R08: 0000000000000286 R09: 0000000000000000 R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007effbd303f60 R15: 00007ffe71ffd958 rcu: rcu_preempt kthread starved for 10528 jiffies! g8669 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:27680 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-rc7-syzkaller-00254-g528dd46d0fc3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 c8 d4 1b 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 78 72 b3 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0000:ffffffff8d807d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8ae7e759 RDX: 0000000000000001 RSI: ffff8880196e2000 RDI: ffff8880196e2064 RBP: ffff8880196e2064 R08: 0000000000000001 R09: ffffed1017246fdd R10: ffff8880b9237eeb R11: 0000000000000000 R12: ffff888019fea800 R13: ffffffff8e745940 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f34f64cfd38 CR3: 000000006a476000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:702 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x313/0x3f0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 rest_init+0x16b/0x2b0 init/main.c:747 start_kernel+0x3df/0x4c0 init/main.c:1103 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148