Re: [syzbot] [mm?] [input?] [usb?] INFO: rcu detected stall in asm_exc_page_fault

[syzbot <syzbot+360faf5c01a5be55581d@syzkaller.appspotmail.com>]

>>
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit:    90d35da658da Linux 6.8-rc7
>> git tree:       upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=122f6f6a180000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=119d08814b43915b
>> dashboard link: https://syzkaller.appspot.com/bug?extid=360faf5c01a5be55581d
>> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=124056de180000
>>
>> Downloadable assets:
>> disk image: https://storage.googleapis.com/syzbot-assets/fb2c1adf4ec3/disk-90d35da6.raw.xz
>> vmlinux: https://storage.googleapis.com/syzbot-assets/09c5b88a8ceb/vmlinux-90d35da6.xz
>> kernel image: https://storage.googleapis.com/syzbot-assets/5e5cbc312e49/bzImage-90d35da6.xz
>>
>> IMPORTANT: if you fix the issue, please add the following tag to the commit:
>> Reported-by: syzbot+360faf5c01a5be55581d@syzkaller.appspotmail.com
>
>
> #syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

want either no args or 2 args (repo, branch), got 1

> master
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 7019a40457a6..69e344f07e68 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -9233,6 +9233,7 @@ void show_state_filter(unsigned int state_filter)
>                  */
>                 touch_nmi_watchdog();
>                 touch_all_softlockup_watchdogs();
> +               rcu_cpu_stall_reset();
>                 if (state_filter_match(state_filter, p))
>                         sched_show_task(p);
>
>         }
>
>
>>
>> rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
>>  1-....
>>  } 4831 jiffies s: 1849 root: 0x2/.
>> rcu: blocking rcu_node structures (internal RCU debug):
>> Sending NMI from CPU 0 to CPUs 1:
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>> NMI backtrace for cpu 1
>> CPU: 1 PID: 5232 Comm: syz-executor.3 Not tainted 6.8.0-rc7-syzkaller #0
>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
>> RIP: 0010:format_decode+0x546/0x1bb0
>> Code: 85 96 01 00 00 45 84 ff 0f 84 8d 01 00 00 48 bb 00 ff ff ff 00 ff ff ff 48 8b 44 24 20 42 0f b6 04 30 84 c0 0f 85 4d 10 00 00 <48> 8b 54 24 48 48 21 da 48 8b 44 24 28 42 0f b6 04 30 84 c0 48 8d
>> RSP: 0000:ffffc900001efa20 EFLAGS: 00000046
>> RAX: 0000000000000000 RBX: ffffff00ffffff00 RCX: ffff8880219e0000
>> RDX: ffff8880219e0000 RSI: 0000000000000025 RDI: 0000000000000000
>> RBP: ffffc900001efb10 R08: ffffffff8b57a4c8 R09: ffffffff8b57a1aa
>> R10: 0000000000000002 R11: ffff8880219e0000 R12: ffffffff8bab75e6
>> R13: ffffffff8bab75e6 R14: dffffc0000000000 R15: 0000000000000025
>> FS:  0000555555c82480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
>> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00007f74dc087056 CR3: 0000000021bc6000 CR4: 00000000003506f0
>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>> Call Trace:
>>  <NMI>
>>  </NMI>
>>  <IRQ>
>>  vsnprintf+0x14f/0x1da0 lib/vsprintf.c:2776
>>  sprintf+0xda/0x120 lib/vsprintf.c:3028
>>  print_time kernel/printk/printk.c:1324 [inline]
>>  info_print_prefix+0x16b/0x310 kernel/printk/printk.c:1350
>>  record_print_text kernel/printk/printk.c:1399 [inline]
>>  printk_get_next_message+0x408/0xce0 kernel/printk/printk.c:2828
>>  console_emit_next_record kernel/printk/printk.c:2868 [inline]
>>  console_flush_all+0x42d/0xec0 kernel/printk/printk.c:2967
>>  console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3036
>>  vprintk_emit+0x508/0x720 kernel/printk/printk.c:2303
>>  _printk+0xd5/0x120 kernel/printk/printk.c:2328
>>  printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline]
>>  show_trace_log_lvl+0x438/0x520 arch/x86/kernel/dumpstack.c:285
>>  sched_show_task+0x50c/0x6d0 kernel/sched/core.c:9171
>>  show_state_filter+0x19e/0x270 kernel/sched/core.c:9216
>>  kbd_keycode drivers/tty/vt/keyboard.c:1524 [inline]
>>  kbd_event+0x30fa/0x4910 drivers/tty/vt/keyboard.c:1543
>>  input_to_handler drivers/input/input.c:132 [inline]
>>  input_pass_values+0x945/0x1200 drivers/input/input.c:161
>>  input_event_dispose drivers/input/input.c:378 [inline]
>>  input_handle_event drivers/input/input.c:406 [inline]
>>  input_repeat_key+0x3fd/0x6c0 drivers/input/input.c:2263
>>  call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700
>>  expire_timers kernel/time/timer.c:1751 [inline]
>>  __run_timers+0x621/0x830 kernel/time/timer.c:2038
>>  run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051
>>  __do_softirq+0x2bb/0x942 kernel/softirq.c:553
>>  invoke_softirq kernel/softirq.c:427 [inline]
>>  __irq_exit_rcu+0xf1/0x1c0 kernel/softirq.c:632
>>  irq_exit_rcu+0x9/0x30 kernel/softirq.c:644
>>  sysvec_apic_timer_interrupt+0x97/0xb0 arch/x86/kernel/apic/apic.c:1076
>>  </IRQ>
>>  <TASK>
>>  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
>> RIP: 0010:page_table_check_set+0x58/0x700 mm/page_table_check.c:109
>> Code: 95 ff 85 ed 0f 84 5f 03 00 00 49 bf 00 00 00 00 00 fc ff df 48 c1 e3 06 48 bd 00 00 00 00 00 ea ff ff 48 8d 3c 2b 48 89 3c 24 <e8> 33 e9 ff ff 49 89 c6 4c 8d 64 2b 08 4c 89 e5 48 c1 ed 03 42 80
>> RSP: 0000:ffffc90004d0f650 EFLAGS: 00000202
>> RAX: 0000000000000000 RBX: 0000000001c8ae80 RCX: ffff8880219e0000
>> RDX: ffff8880219e0000 RSI: 0000000000000001 RDI: ffffea0001c8ae80
>> RBP: ffffea0000000000 R08: ffffffff81fdf590 R09: 1ffffffff1f0880d
>> R10: dffffc0000000000 R11: fffffbfff1f0880e R12: 0000000000000000
>> R13: 0000000000000001 R14: 00000000722ba025 R15: dffffc0000000000
>>  __page_table_check_ptes_set+0x220/0x280 mm/page_table_check.c:196
>>  page_table_check_ptes_set include/linux/page_table_check.h:74 [inline]
>>  set_ptes include/linux/pgtable.h:241 [inline]
>>  set_pte_range+0x885/0x8b0 mm/memory.c:4549
>>  filemap_map_order0_folio mm/filemap.c:3513 [inline]
>>  filemap_map_pages+0xee2/0x1830 mm/filemap.c:3559
>>  do_fault_around mm/memory.c:4716 [inline]
>>  do_read_fault mm/memory.c:4749 [inline]
>>  do_fault mm/memory.c:4888 [inline]
>>  do_pte_missing mm/memory.c:3745 [inline]
>>  handle_pte_fault mm/memory.c:5164 [inline]
>>  __handle_mm_fault+0x485d/0x72d0 mm/memory.c:5305
>>  handle_mm_fault+0x27e/0x770 mm/memory.c:5470
>>  do_user_addr_fault arch/x86/mm/fault.c:1355 [inline]
>>  handle_page_fault arch/x86/mm/fault.c:1498 [inline]
>>  exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1554
>>  asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
>> RIP: 0033:0x7f74dc087080
>> Code: Unable to access opcode bytes at 0x7f74dc087056.
>> RSP: 002b:00007ffe028d3bb8 EFLAGS: 00010246
>> RAX: 00007f74dcdfb9d0 RBX: 00007f74dcdfb6c0 RCX: 00007f74dc07de67
>> RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f74dcdfb6c0
>> RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
>> R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffe028d3e60
>> R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
>>  </TASK>
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:kworker/u4:0    state:I stack:24400 pid:11    tgid:11    ppid:2      flags:0x00004000
>> Workqueue:  0x0 (events_unbound)
>> Call Trace:
>>  <TASK>
>>  context_switch kernel/sched/core.c:5400 [inline]
>>  __schedule+0x177f/0x49a0 kernel/sched/core.c:6727
>>  __schedule_loop kernel/sched/core.c:6802 [inline]
>>  schedule+0x149/0x260 kernel/sched/core.c:6817
>>  worker_thread+0xc26/0x1000 kernel/workqueue.c:2802
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:kworker/u4:1    state:I stack:23344 pid:12    tgid:12    ppid:2      flags:0x00004000
>> Workqueue:  0x0 (bat_events)
>> Call Trace:
>>  <TASK>
>>  context_switch kernel/sched/core.c:5400 [inline]
>>  __schedule+0x177f/0x49a0 kernel/sched/core.c:6727
>>  __schedule_loop kernel/sched/core.c:6802 [inline]
>>  schedule+0x149/0x260 kernel/sched/core.c:6817
>>  worker_thread+0xc26/0x1000 kernel/workqueue.c:2802
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:kworker/R-mm_pe state:I stack:28752 pid:13    tgid:13    ppid:2      flags:0x00004000
>> Call Trace:
>>  <TASK>
>>  context_switch kernel/sched/core.c:5400 [inline]
>>  __schedule+0x177f/0x49a0 kernel/sched/core.c:6727
>>  __schedule_loop kernel/sched/core.c:6802 [inline]
>>  schedule+0x149/0x260 kernel/sched/core.c:6817
>>  rescuer_thread+0xc45/0xda0 kernel/workqueue.c:2937
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:rcu_tasks_kthre state:I stack:27448 pid:14    tgid:14    ppid:2      flags:0x00004000
>> Call Trace:
>>  <TASK>
>>  context_switch kernel/sched/core.c:5400 [inline]
>>  __schedule+0x177f/0x49a0 kernel/sched/core.c:6727
>>  __schedule_loop kernel/sched/core.c:6802 [inline]
>>  schedule+0x149/0x260 kernel/sched/core.c:6817
>>  rcu_tasks_one_gp+0x7f5/0xda0 kernel/rcu/tasks.h:578
>>  rcu_tasks_kthread+0x186/0x1b0 kernel/rcu/tasks.h:625
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:rcu_tasks_trace state:I stack:27144 pid:15    tgid:15    ppid:2      flags:0x00004000
>> Call Trace:
>>  <TASK>
>>  context_switch kernel/sched/core.c:5400 [inline]
>>  __schedule+0x177f/0x49a0 kernel/sched/core.c:6727
>>  __schedule_loop kernel/sched/core.c:6802 [inline]
>>  schedule+0x149/0x260 kernel/sched/core.c:6817
>>  rcu_tasks_one_gp+0x7f5/0xda0 kernel/rcu/tasks.h:578
>>  rcu_tasks_kthread+0x186/0x1b0 kernel/rcu/tasks.h:625
>>  kthread+0x2ef/0x390 kernel/kthread.c:388
>>  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
>>  ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
>>  </TASK>
>> task:ksoftirqd/0
>>
>>
>> ---
>> This report is generated by a bot. It may contain errors.
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>>
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>>
>> If the report is already addressed, let syzbot know by replying with:
>> #syz fix: exact-commit-title
>>
>> If you want syzbot to run the reproducer, reply with:
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>>
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>>
>> If the report is a duplicate of another one, reply with:
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>>
>> If you want to undo deduplication, reply with:
>> #syz undup
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