syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6229/1:b..l
rcu: 	(detected by 0, t=10505 jiffies, g=12473, q=465 ncpus=2)
task:rm              state:R  running task     stack:23680 pid:6229  tgid:6229  ppid:6192   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732
 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:1688 [inline]
 zap_pmd_range mm/memory.c:1736 [inline]
 zap_pud_range mm/memory.c:1765 [inline]
 zap_p4d_range mm/memory.c:1786 [inline]
 unmap_page_range+0x3818/0x42c0 mm/memory.c:1807
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1897
 exit_mmap+0x264/0xc80 mm/mmap.c:3412
 __mmput+0x115/0x380 kernel/fork.c:1345
 exit_mm+0x220/0x310 kernel/exit.c:571
 do_exit+0x9b2/0x27f0 kernel/exit.c:869
 do_group_exit+0x207/0x2c0 kernel/exit.c:1031
 __do_sys_exit_group kernel/exit.c:1042 [inline]
 __se_sys_exit_group kernel/exit.c:1040 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f4e6ce48a90
RSP: 002b:00007ffd134773c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f4e6cf39860 RCX: 00007f4e6ce48a90
RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00007f4e6cf39860 R08: 00007ffd13477240 R09: 00007ffd13477320
R10: 00007ffd13477280 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4e6cf3d658 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10484 jiffies! g12473 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=8665
rcu: rcu_preempt kthread starved for 10485 jiffies! g12473 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:25816 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>
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: 6233 Comm: syz.4.261 Not tainted 6.11.0-rc2-syzkaller-00042-gcf6d429eb656 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1705 [inline]
RIP: 0010:__hrtimer_run_queues+0x696/0xd50 kernel/time/hrtimer.c:1753
Code: 70 8d 36 0a 31 ff 44 89 ee e8 b6 b9 12 00 45 85 ed 74 4e 49 bd 00 00 00 00 00 fc ff df 48 8b 84 24 b8 00 00 00 42 0f b6 04 28 <84> c0 48 8b 54 24 30 0f 85 73 02 00 00 0f b6 1a 89 de 83 e6 01 31
RSP: 0018:ffffc90000a18d60 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffff8880b932c9c8 RCX: 0000000000000001
RDX: ffff88802b2b5a00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000a18ea8 R08: ffffffff8180c0da R09: fffff52000143188
R10: dffffc0000000000 R11: fffff52000143188 R12: 1ffff1101726593b
R13: dffffc0000000000 R14: ffff88807ceb1340 R15: ffff8880b932c880
FS:  00007ff1168d36c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020025000 CR3: 000000007de26000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5062
Code: c9 50 e8 d9 b6 0b 00 48 83 c4 08 4c 89 f7 e8 7d 38 00 00 e9 de 04 00 00 4c 89 f7 e8 00 4c 53 0a e8 fb d6 36 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc90004457568 EFLAGS: 00000286
RAX: 461fdb392b598300 RBX: ffff88802b2b5a00 RCX: ffffffff94ce6903
RDX: dffffc0000000000 RSI: ffffffff8bead560 RDI: ffffffff8c3f8b40
RBP: ffffc900044575b0 R08: ffffffff8ff699ef R09: 1ffffffff1fed33d
R10: dffffc0000000000 R11: fffffbfff1fed33e R12: 1ffff11017267eeb
R13: dffffc0000000000 R14: ffff8880b923e9c0 R15: ffff8880b933f758
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0x17b6/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2557
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x355/0x620 kernel/sched/completion.c:148
 rdmsr_safe_on_cpu+0x16c/0x310 arch/x86/lib/msr-smp.c:181
 msr_read+0x160/0x260 arch/x86/kernel/msr.c:66
 vfs_read+0x204/0xbc0 fs/read_write.c:474
 ksys_read+0x1a0/0x2c0 fs/read_write.c:619
 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: 0033:0x7ff115b779f9
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:00007ff1168d3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007ff115d05f80 RCX: 00007ff115b779f9
RDX: 0000000000018ff8 RSI: 0000000020019680 RDI: 0000000000000003
RBP: 00007ff115be58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff115d05f80 R15: 00007fffe0cb5948
 </TASK>