From: "Patrik, Kluba" <pkluba@dension.com>
To: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Subject: bug: keep_bootcon and early printk together can lead to (invisible) kernel panic
Date: Thu, 21 Feb 2013 15:37:17 +0100 [thread overview]
Message-ID: <20130221153717.31400a88.pkluba@dension.com> (raw)
Hi!
I had a silent lockup on one of our embedded system under development.
It was not easy to track it down, so here's what I discovered, in case
somebody runs into similar trouble.
Using 'keep_bootcon' command line parameter, and enabling early printk
can lead to a kernel panic. At least on MIPS, it does. The problem is
that in arch/mips/kernel/early_printk.c everything is declared as
__init and __initdata, so they are being freed, when the kernel
frees .init.* sections. If 'keep_bootcon' is given, the early console
does not get unregistered, and the entry in the console_drivers list
can point (will, believe me) to garbage data. It's up to you to imagine
the effects...
Regards,
Patrik
--
Patrik KLUBA
Software Developer at
DENSION Audio Systems Ltd.
H-1116 Budapest, Sztregova u. 1
Phone: +36 1 463 0470
Fax: +36 1 463 0479
Web: www.dension.com
next reply other threads:[~2013-02-21 14:43 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-21 14:37 Patrik, Kluba [this message]
2013-02-21 15:46 ` bug: keep_bootcon and early printk together can lead to (invisible) kernel panic Aaro Koskinen
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=20130221153717.31400a88.pkluba@dension.com \
--to=pkluba@dension.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@linux-mips.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.