From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>,
Pekka Enberg <penberg@cs.helsinki.fi>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH -tip] kmemcheck: fix crash in PnP BIOS calls
Date: Sun, 5 Oct 2008 19:15:55 +0100 [thread overview]
Message-ID: <20081005191555.5715da29@lxorguk.ukuu.org.uk> (raw)
In-Reply-To: <20081005172504.GB24825@localhost.localdomain>
> It turns out that BIOS calls are made with a different code segment. So
> when kmemcheck tries to dereference the EIP/RIP (using the kernel data
> segment register), we get the unhandled page fault.
>
> I think we can solve this by verifying (in the page fault handler) that
> the faulting code is using the kernel CS.
That isn't an entirely safe assumption and some services such as BIOS32
are 32bit. Would it be better wrap BIOS calls with a kmemcheck wrapper
which changes the way kmemcheck works/dumps stuff and also gives you a
hook after BIOS calls to do stuff like corruption scans or change
detection on kernel pages ?
Alan
next prev parent reply other threads:[~2008-10-05 18:17 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-05 17:25 Vegard Nossum
2008-10-05 18:15 ` Alan Cox [this message]
2008-10-05 19:04 ` Vegard Nossum
2008-10-05 19:10 ` Alan Cox
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=20081005191555.5715da29@lxorguk.ukuu.org.uk \
--to=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=penberg@cs.helsinki.fi \
--cc=vegard.nossum@gmail.com \
/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®