syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=100c/1/0x4000000000000000 softirq=36707/36707 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9723/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=35165, q=12 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9730 Comm: syz.0.1055 Not tainted 6.12.0-rc4-syzkaller-00245-gb423f5a9a61f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:737
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 bc ac 80 00 48 c7 c3 98 7e 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 22 8b 03 65 ff 0d e1 ff 88 7e 74 10 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90000a18d40 EFLAGS: 00000802
RAX: 0000000000000000 RBX: ffff8880b8737e98 RCX: ffffffff818244fe
RDX: ffff888030fc3c00 RSI: ffffffff8c602f40 RDI: ffffffff8c602f00
RBP: ffffc90000a18ea8 R08: ffffffff81824524 R09: 1ffffffff2037acd
R10: dffffc0000000000 R11: fffffbfff2037ace R12: 1ffff110170e593b
R13: ffffffff89c3d070 R14: ffffffff8e309a58 R15: dffffc0000000000
FS:  00007f08cd02f6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fed836b1f98 CR3: 0000000065844000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_hrtimer_expire_entry include/trace/events/timer.h:259 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x4ee/0xd50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829
Code: 2b 00 74 08 4c 89 f7 e8 da 2a 8b 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:ffffc900036b75e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920006d6ec8 RCX: 7732fe7cae252500
RDX: dffffc0000000000 RSI: ffffffff8c0adcc0 RDI: ffffffff8c602f60
RBP: ffffc900036b7738 R08: ffffffff94297807 R09: 1ffffffff2852f00
R10: dffffc0000000000 R11: fffffbfff2852f01 R12: 1ffff920006d6ec4
R13: dffffc0000000000 R14: ffffc900036b7640 R15: 0000000000000246
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:375
 pte_offset_map_lock include/linux/mm.h:3014 [inline]
 follow_page_pte+0x129/0x2010 mm/gup.c:846
 follow_pmd_mask mm/gup.c:969 [inline]
 follow_pud_mask mm/gup.c:1021 [inline]
 follow_p4d_mask mm/gup.c:1038 [inline]
 follow_page_mask mm/gup.c:1081 [inline]
 __get_user_pages+0xb75/0x48d0 mm/gup.c:1483
 populate_vma_page_range+0x264/0x330 mm/gup.c:1923
 __mm_populate+0x27a/0x460 mm/gup.c:2026
 mm_populate include/linux/mm.h:3371 [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: 0033:0x7f08cc17e719
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:00007f08cd02f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f08cc335f80 RCX: 00007f08cc17e719
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007f08cc1f132e R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f08cc335f80 R15: 00007fff7c628e08
 </TASK>
task:syz.2.1052      state:R  running task     stack:23616 pid:9723  tgid:9722  ppid:5833   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x185a/0x4b70 kernel/sched/core.c:6690
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 zap_pte_range mm/memory.c:1691 [inline]
 zap_pmd_range mm/memory.c:1739 [inline]
 zap_pud_range mm/memory.c:1768 [inline]
 zap_p4d_range mm/memory.c:1789 [inline]
 unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900
 exit_mmap+0x275/0xc40 mm/mmap.c:1874
 __mmput+0x115/0x380 kernel/fork.c:1347
 exit_mm+0x220/0x310 kernel/exit.c:571
 do_exit+0x9b2/0x28e0 kernel/exit.c:926
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 get_signal+0x16a3/0x1740 kernel/signal.c:2917
 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: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: 0033:0x7f02d457e719
RSP: 002b:00007f02d5384038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 0000000000000024 RBX: 00007f02d4735f80 RCX: 00007f02d457e719
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007f02d45f132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f02d4735f80 R15: 00007ffda6439a08
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g35165 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=28942
rcu: rcu_preempt kthread starved for 10502 jiffies! g35165 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:24176 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x185a/0x4b70 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 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
 </TASK>