mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "Maciej W. Rozycki" <macro@linux-mips.org>
To: James Hogan <james.hogan@imgtec.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>,
	Ralf Baechle <ralf@linux-mips.org>,
	David Daney <david.daney@cavium.com>,
	linux-mips@linux-mips.org, linux-kernel@vger.kernel.org,
	Hemmo Nieminen <hemmo.nieminen@iki.fi>,
	stable@vger.kernel.org
Subject: Re: [PATCH v2 2/2] MIPS: fix kernel lockup or crash after CPU offline/online
Date: Fri, 30 Jan 2015 12:47:39 +0000 (GMT)	[thread overview]
Message-ID: <alpine.LFD.2.11.1501301242080.28301@eddie.linux-mips.org> (raw)
In-Reply-To: <54CB5B59.5050203@imgtec.com>

On Fri, 30 Jan 2015, James Hogan wrote:

> >  Hmm, why can a call to `printk' cause a TLB miss, what's so special about 
> > this function?  Does it use kernel mapped addresses for any purpose such 
> > as `vmalloc'?
> 
> It would be the fact netconsole (or whatever other console is in use) is
> built as a kernel module, memory for which is allocated from the vmalloc
> area.

 Ah, I see, thanks for enlightening me.  But in that case wouldn't it be 
possible to postpone console output from `printk' until it is safe to 
access the device?  In a manner similar to how for example we handle calls 
to `printk' made from the hardirq context.  That would make things less 
fragile.

  Maciej

  reply	other threads:[~2015-01-30 12:47 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-15 21:01 [PATCH v2 1/2] MIPS: OCTEON: fix kernel crash when offlining a CPU Aaro Koskinen
2015-01-15 21:01 ` [PATCH v2 2/2] MIPS: fix kernel lockup or crash after CPU offline/online Aaro Koskinen
2015-01-30  9:25   ` Maciej W. Rozycki
2015-01-30 10:22     ` James Hogan
2015-01-30 12:47       ` Maciej W. Rozycki [this message]
2015-01-30 14:59         ` James Hogan
2015-01-30 17:55           ` Aaro Koskinen
2015-01-30 18:23             ` James Hogan
2015-01-30 18:53               ` Maciej W. Rozycki

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=alpine.LFD.2.11.1501301242080.28301@eddie.linux-mips.org \
    --to=macro@linux-mips.org \
    --cc=aaro.koskinen@iki.fi \
    --cc=david.daney@cavium.com \
    --cc=hemmo.nieminen@iki.fi \
    --cc=james.hogan@imgtec.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@linux-mips.org \
    --cc=ralf@linux-mips.org \
    --cc=stable@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®