rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=477c/1/0x4000000000000000 softirq=33881/33881 fqs=1 rcu: (detected by 1, t=10502 jiffies, g=28877, q=178 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10195 Comm: syz.8.1254 Not tainted 6.13.0-rc3-syzkaller-00062-gc061cf420ded #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:hlock_class+0xb/0x130 kernel/locking/lockdep.c:222 Code: 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 53 <48> 89 fb 48 83 c7 20 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 RSP: 0018:ffffc90000007bd8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000080000 RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888030580b08 RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff2dca199 R10: ffffffff96e50ccf R11: 0000000000000001 R12: 0000000000000002 R13: ffff888030580000 R14: 000000000000006f R15: ffff888030580b08 FS: 00007fa0db93e6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202b5000 CR3: 000000004ba6a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_wait_context kernel/locking/lockdep.c:4851 [inline] __lock_acquire+0x44d/0x3c40 kernel/locking/lockdep.c:5176 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1743 [inline] __hrtimer_run_queues+0x2be/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0xd/0xc0 kernel/rcu/tree.c:737 Code: 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 65 ff 05 fb 3b 84 7e be f2 a9 09 48 c7 c3 68 7f 03 00 83 f8 07 89 c5 0f 87 82 00 00 RSP: 0018:ffffc900035978c0 EFLAGS: 00000283 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8175dc4c RDX: fffffbfff20be64b RSI: 0000000000000008 RDI: ffffffff905f3250 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff20be64a R10: ffffffff905f3257 R11: 0000000000000003 R12: 0000000000000000 R13: 000000000003d90c R14: 0000000000000000 R15: 0000000000000000 trace_lock_acquire+0x14e/0x1f0 include/trace/events/lock.h:24 lock_acquire+0x2f/0xb0 kernel/locking/lockdep.c:5820 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] count_memcg_events_mm.constprop.0+0x40/0x340 include/linux/memcontrol.h:994 count_memcg_event_mm include/linux/memcontrol.h:1004 [inline] mm_account_fault mm/memory.c:5978 [inline] handle_mm_fault+0x5cc/0xaa0 mm/memory.c:6138 do_user_addr_fault+0x7a3/0x13f0 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:ffffc90003597b20 EFLAGS: 00050206 RAX: 0000000000000001 RBX: 00000000202b5000 RCX: 0000000000001000 RDX: 0000000000000000 RSI: 00000000202b5000 RDI: ffff888078fdc000 RBP: 0000000000001000 R08: 0000000000000001 R09: ffffed100f1fb9ff R10: ffff888078fdcfff R11: 0000000000000000 R12: 0000000000000000 R13: ffff888078fdc000 R14: dffffc0000000000 R15: 00000000202b5000 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] _inline_copy_from_user include/linux/uaccess.h:178 [inline] _copy_from_user+0x9a/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] snd_rawmidi_kernel_write1+0x4f9/0x880 sound/core/rawmidi.c:1557 snd_rawmidi_write+0x267/0xbe0 sound/core/rawmidi.c:1626 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x207/0x250 fs/read_write.c:731 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: 0033:0x7fa0dab85d29 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:00007fa0db93e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa0dad75fa0 RCX: 00007fa0dab85d29 RDX: 00000000d332556e RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007fa0dac01a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa0dad75fa0 R15: 00007ffe32dd5318 rcu: rcu_preempt kthread starved for 10500 jiffies! g28877 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:28472 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 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: 1 UID: 0 PID: 10198 Comm: syz.7.1253 Not tainted 6.13.0-rc3-syzkaller-00062-gc061cf420ded #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x458/0x1300 kernel/smp.c:884 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ba 0e 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90003607c18 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff8880b86469c0 RCX: ffffc9001bb8a000 RDX: 0000000000080000 RSI: ffffffff818e0696 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000002 R12: ffffed10170c8d39 R13: 0000000000000001 R14: ffff8880b86469c8 R15: ffff8880b873fe40 FS: 00007fdbeb09d6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000240 CR3: 000000002875a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: clock_was_set+0x646/0x850 kernel/time/hrtimer.c:963 do_settimeofday64+0x305/0x4c0 kernel/time/timekeeping.c:1442 do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:195 __do_sys_clock_settime kernel/time/posix-timers.c:1135 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1119 [inline] __x64_sys_clock_settime+0x1bf/0x2a0 kernel/time/posix-timers.c:1119 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: 0033:0x7fdbea185d29 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:00007fdbeb09d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007fdbea375fa0 RCX: 00007fdbea185d29 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000000 RBP: 00007fdbea201a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdbea375fa0 R15: 00007ffed3cd99f8