rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5649/1:b..l rcu: (detected by 1, t=10503 jiffies, g=8349, q=1034 ncpus=2) task:syz.4.88 state:R running task stack:23928 pid:5649 tgid:5648 ppid:5225 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5763 Code: 2b 00 74 08 4c 89 f7 e8 7a da 87 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:ffffc90009d2f600 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920013a5ecc RCX: 6b430c6759b70e00 RDX: dffffc0000000000 RSI: ffffffff8beae6c0 RDI: ffffffff8c3f9000 RBP: ffffc90009d2f748 R08: ffffffff934f1847 R09: 1ffffffff269e308 R10: dffffc0000000000 R11: fffffbfff269e309 R12: 1ffff920013a5ec8 R13: dffffc0000000000 R14: ffffc90009d2f660 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] count_memcg_event_mm+0xb1/0x420 include/linux/memcontrol.h:1017 mm_account_fault mm/memory.c:5699 [inline] handle_mm_fault+0x149a/0x1880 mm/memory.c:5859 faultin_page mm/gup.c:1194 [inline] __get_user_pages+0x6ec/0x16a0 mm/gup.c:1493 populate_vma_page_range+0x264/0x330 mm/gup.c:1932 __mm_populate+0x27a/0x460 mm/gup.c:2035 mm_populate include/linux/mm.h:3415 [inline] vm_mmap_pgoff+0x2c3/0x3d0 mm/util.c:593 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6c00b779f9 RSP: 002b:00007f6c01a08038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f6c00d05f80 RCX: 00007f6c00b779f9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f6c00be58ee R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6c00d05f80 R15: 00007ffcaca95a38 rcu: rcu_preempt kthread starved for 238 jiffies! g8349 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:26576 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 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: CPU: 1 UID: 0 PID: 5643 Comm: syz.0.85 Not tainted 6.11.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 1a 50 b8 f5 48 89 df e8 f2 92 b9 f5 e8 2d 49 e3 f5 fb bf 01 00 00 00 02 5e ab f5 65 8b 05 53 45 4c 74 85 c0 74 06 5b c3 cc cc cc cc RSP: 0018:ffffc9000d3bfc70 EFLAGS: 00000282 RAX: 15e2dee7414e6b00 RBX: ffff888025b6a500 RCX: ffffffff94ce9903 RDX: dffffc0000000000 RSI: ffffffff8bead540 RDI: 0000000000000001 RBP: ffffc9000d3bfdb0 R08: ffffffff8ff6a22f R09: 1ffffffff1fed445 R10: dffffc0000000000 R11: fffffbfff1fed446 R12: 0000000000000011 R13: 1ffff11004b6d4f3 R14: ffff888025b6a798 R15: ffff888025b6a500 FS: 00007f90eab7a6c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32016ff8 CR3: 00000000484b4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x14d1/0x1730 kernel/signal.c:2920 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f90e9d779f9 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:00007f90eab7a0e8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 00007f90e9f05f88 RCX: 00007f90e9d779f9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f90e9f05f88 RBP: 00007f90e9f05f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f90e9f05f8c R13: 0000000000000000 R14: 00007fff95a9fe00 R15: 00007fff95a9fee8