rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=36537, q=423 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4294988506-4294978006), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10500 jiffies! g36537 f0x2 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:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11251 Comm: syz.1.1143 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_acquire+0xea5/0x2100 Code: eb 8a 89 d8 25 ff 1f 00 00 c1 eb 03 81 e3 00 60 00 00 09 c3 4c 89 f0 48 c1 e8 20 29 c3 89 c1 c1 c1 04 31 d9 44 01 f0 41 29 ce <89> ca c1 c2 06 44 31 f2 01 c1 29 d0 89 d6 c1 c6 08 31 c6 01 ca 29 RSP: 0018:ffffc90000007930 EFLAGS: 00000083 RAX: 000000000424e9ed RBX: 000000002a81e2f0 RCX: 000000007d6033fd RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000 RBP: ffff88802b6fe580 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: ffff88802b6fda00 R13: ffff88802b6fda00 R14: 00000000b14698e0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 000000007701a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475 __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 2a a0 88 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000e447020 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92001c88e10 RCX: ffff88802b6fe4d8 RDX: dffffc0000000000 RSI: ffffffff8c0aaae0 RDI: ffffffff8c5edd60 RBP: ffffc9000e447178 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: 1ffff92001c88e0c R13: dffffc0000000000 R14: ffffc9000e447080 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget+0x31/0x180 include/linux/percpu-refcount.h:266 css_tryget include/linux/cgroup_refcnt.h:45 [inline] get_mem_cgroup_from_objcg+0x108/0x1d0 include/linux/memcontrol.h:501 uncharge_folio+0x12c/0x680 mm/memcontrol.c:4673 __mem_cgroup_uncharge_folios+0xdf/0x1c0 mm/memcontrol.c:4734 mem_cgroup_uncharge_folios include/linux/memcontrol.h:677 [inline] folios_put_refs+0x764/0x860 mm/swap.c:961 free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:335 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x496/0xc20 mm/mmap.c:1681 __mmput+0x115/0x3b0 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:570 do_exit+0x9ad/0x28e0 kernel/exit.c:925 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3017 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa52e185d29 Code: Unable to access opcode bytes at 0x7fa52e185cff. RSP: 002b:00007fa52eff7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: 0000000000002e00 RBX: 00007fa52e376080 RCX: 00007fa52e185d29 RDX: 0000000000000000 RSI: 000000000000000b RDI: 000000000000000a RBP: 00007fa52e201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa52e376080 R15: 00007ffce8b76ae8