mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: David Miller <davem@davemloft.net>
To: mroos@linux.ee
Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org
Subject: Re: RCU detected CPU 0 stall after panic on sparc64
Date: Sat, 12 Dec 2009 01:40:02 -0800 (PST)	[thread overview]
Message-ID: <20091212.014002.173528710.davem@davemloft.net> (raw)
In-Reply-To: <alpine.SOC.1.00.0912121049030.26625@math.ut.ee>

From: Meelis Roos <mroos@linux.ee>
Date: Sat, 12 Dec 2009 10:54:19 +0200 (EET)

> I tried 2.6.32 git gaad3bf0 on a SMP sparc64 machine (Ultra Enterprise 
> 250). For some reason my disks were not found (not important in this 
> bugreport) and this resulted in panic (cannnot mount root). However, the 
> machine kept going and got the below messages (RCU detected CPU 0 stall 
> (t=1000 jiffies)) from timer interrupts.
> 
> This seems to be like a bug in RCU vs panic.

It's normal actually.  A panic() just loops forever and the cpu never
goes through an RCU grace period again as a result, and this triggers
the debugging timer that detects this condition.

Probably the panic() code should disable that assertion check.

  reply	other threads:[~2009-12-12  9:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-12  8:54 Meelis Roos
2009-12-12  9:40 ` David Miller [this message]
2009-12-14 20:25   ` Paul E. McKenney
2009-12-14 21:02     ` David Miller
2009-12-14 23:15       ` Paul E. McKenney

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=20091212.014002.173528710.davem@davemloft.net \
    --to=davem@davemloft.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mroos@linux.ee \
    --cc=sparclinux@vger.kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®