All of lore.kernel.org
 help / color / mirror / Atom feed
From: John Ogness <john.ogness@linutronix.de>
To: lkp@lists.01.org
Subject: Re: [printk] b031a684bf: INFO:rcu_tasks_detected_stalls_on_tasks
Date: Wed, 27 Jan 2021 22:28:59 +0106	[thread overview]
Message-ID: <87bldaaxcc.fsf@jogness.linutronix.de> (raw)
In-Reply-To: <YA+gAV1kW8Ru1+Bo@jagdpanzerIV.localdomain>

[-- Attachment #1: Type: text/plain, Size: 1438 bytes --]

On 2021-01-26, Sergey Senozhatsky <sergey.senozhatsky@gmail.com> wrote:
> AFAIU this is just 'modprobe rcutorture'

I was finally able to trigger this by using my workstation:

    Intel(R) Core(TM) i5-8259U CPU @ 2.30GHz
    Debian/buster
    QEMU 3.1.0 (Debian 1:3.1+dfsg-8+deb10u8)

instead of my build server:

    Intel(R) Xeon(R) CPU E5-2697 v4 @ 2.30GHz
    Debian/bullseye
    QEMU 5.2.0 (Debian 1:5.2+dfsg-3)

I don't know what factors contributed, but I wanted to share my success
in reproducing the reported problem. Instead of using lkp, I am manually
booting with:

$ kvm -cpu host -smp 2 -m 8G -nographic \
      -kernel bzImage -append "console=ttyS0,115200 loglevel=6" \
      -initrd initrd

My initrd is a minimal busybox rootfs that runs:

# modprobe rcutorture onoff_interval=3 onoff_holdoff=30 torture_type=tasks

(Those are the same modprobe parameters used by the lkp job.)

After about a minute I see:

[   47.268292] tasks-torture: rcu_torture_read_exit: Start of episode
[   51.273365] tasks-torture: rcu_torture_read_exit: End of episode
[   55.823306] smpboot: do_boot_cpu failed(-1) to wakeup CPU#0
[   55.824350] tasks-torture:torture_onoff task: online 0 failed: errno -5
[   55.830661] tasks-torture:torture_onoff task: online 0 failed: errno -5
[   55.848524] tasks-torture:torture_onoff task: online 0 failed: errno -5

I will start to debug this now.

John Ogness

WARNING: multiple messages have this Message-ID (diff)
From: John Ogness <john.ogness@linutronix.de>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	Petr Mladek <pmladek@suse.com>
Cc: kernel test robot <oliver.sang@intel.com>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	lkp@lists.01.org, lkp@intel.com, zhengjun.xing@linux.intel.com
Subject: Re: [printk]  b031a684bf: INFO:rcu_tasks_detected_stalls_on_tasks
Date: Wed, 27 Jan 2021 22:28:59 +0106	[thread overview]
Message-ID: <87bldaaxcc.fsf@jogness.linutronix.de> (raw)
In-Reply-To: <YA+gAV1kW8Ru1+Bo@jagdpanzerIV.localdomain>

On 2021-01-26, Sergey Senozhatsky <sergey.senozhatsky@gmail.com> wrote:
> AFAIU this is just 'modprobe rcutorture'

I was finally able to trigger this by using my workstation:

    Intel(R) Core(TM) i5-8259U CPU @ 2.30GHz
    Debian/buster
    QEMU 3.1.0 (Debian 1:3.1+dfsg-8+deb10u8)

instead of my build server:

    Intel(R) Xeon(R) CPU E5-2697 v4 @ 2.30GHz
    Debian/bullseye
    QEMU 5.2.0 (Debian 1:5.2+dfsg-3)

I don't know what factors contributed, but I wanted to share my success
in reproducing the reported problem. Instead of using lkp, I am manually
booting with:

$ kvm -cpu host -smp 2 -m 8G -nographic \
      -kernel bzImage -append "console=ttyS0,115200 loglevel=6" \
      -initrd initrd

My initrd is a minimal busybox rootfs that runs:

# modprobe rcutorture onoff_interval=3 onoff_holdoff=30 torture_type=tasks

(Those are the same modprobe parameters used by the lkp job.)

After about a minute I see:

[   47.268292] tasks-torture: rcu_torture_read_exit: Start of episode
[   51.273365] tasks-torture: rcu_torture_read_exit: End of episode
[   55.823306] smpboot: do_boot_cpu failed(-1) to wakeup CPU#0
[   55.824350] tasks-torture:torture_onoff task: online 0 failed: errno -5
[   55.830661] tasks-torture:torture_onoff task: online 0 failed: errno -5
[   55.848524] tasks-torture:torture_onoff task: online 0 failed: errno -5

I will start to debug this now.

John Ogness

  reply	other threads:[~2021-01-27 21:22 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-22  8:13 [printk] b031a684bf: INFO:rcu_tasks_detected_stalls_on_tasks kernel test robot
2021-01-22  8:13 ` kernel test robot
2021-01-22 16:21 ` Petr Mladek
2021-01-22 16:21   ` Petr Mladek
2021-01-26  4:52   ` Sergey Senozhatsky
2021-01-26  4:52     ` Sergey Senozhatsky
2021-01-27 21:22     ` John Ogness [this message]
2021-01-27 21:22       ` John Ogness
2021-01-27 23:29       ` John Ogness
2021-01-27 23:29         ` John Ogness
2021-01-28  8:30       ` Sergey Senozhatsky
2021-01-28  8:30         ` Sergey Senozhatsky
2021-01-28 11:26         ` John Ogness
2021-01-28 11:26           ` John Ogness
2021-01-28 14:51           ` Petr Mladek
2021-01-28 14:51             ` Petr Mladek
2021-01-28 15:42             ` John Ogness
2021-01-28 15:42               ` John Ogness
2021-01-28 16:36               ` Petr Mladek
2021-01-28 16:36                 ` Petr Mladek
2021-01-28 17:36                 ` John Ogness
2021-01-28 17:36                   ` John Ogness
2021-01-28 21:38                   ` John Ogness
2021-01-28 21:38                     ` John Ogness
2021-01-23  2:44 ` Sergey Senozhatsky
2021-01-23  2:44   ` Sergey Senozhatsky
2021-02-02 17:13 ` John Ogness
2021-02-02 17:13   ` John Ogness
2021-02-04 21:32   ` John Ogness
2021-02-04 21:32     ` John Ogness
2021-02-05  9:32     ` Petr Mladek
2021-02-05  9:32       ` Petr Mladek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87bldaaxcc.fsf@jogness.linutronix.de \
    --to=john.ogness@linutronix.de \
    --cc=lkp@lists.01.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.