From: Dan Carpenter <dan.carpenter@oracle.com>
To: Joseph Salisbury <joseph.salisbury@canonical.com>
Cc: list@osuosl.org, Jiri Kosina <jkosina@suse.cz>,
Haiyang Zhang <haiyangz@microsoft.com>,
LKML <linux-kernel@vger.kernel.org>,
open@osuosl.org, HID CORE LAYER <linux-input@vger.kernel.org>,
devel@linuxdriverproject.org, thomas@m3y3r.de
Subject: Re: [v3.11][Regression] HID: hyperv: convert alloc+memcpy to memdup
Date: Tue, 17 Sep 2013 00:05:04 +0300 [thread overview]
Message-ID: <20130916210503.GQ25896@mwanda> (raw)
In-Reply-To: <52376ED9.5080208@canonical.com>
On Mon, Sep 16, 2013 at 04:49:29PM -0400, Joseph Salisbury wrote:
> On 09/16/2013 04:38 PM, Dan Carpenter wrote:
> > On Mon, Sep 16, 2013 at 01:42:35PM -0400, Joseph Salisbury wrote:
> >> Reverting the patch changes the driver back to useing kzalloc() and
> >> memcpy() instead of kmemdup. Doing so has uncovered another bug, which
> >> causes an oops on memcpy()[1]. We are in the process of bisecting that
> >> one now and will provide the results.
> > The two bugs are the same it's that the code has shifted a little. Mark
> > the commit as buggy and continue with the git bisect.
> >
> > regards,
> > dan carpenter
> Can you explain a little further? Mark commit a4a23f6 as bad? An
> initial bisect already reported that was the first bad commit, so it
> can't be marked bad. The oops on memcpy() happens after commit a4a23f6
> is reverted. The oops on memcpy() did not happen before a4a23f6 was
> committed, so I assume this new oops was introduced by a change later.
>
> Right now I'm bisecting down the oops on memcpy() by updating the bisect
> with good or bad, depending if the test kernel hit the oops. I then
> revert a4a23f6, so that revert is the HEAD of the tree each time before
> building the kernel again(As long as the commit spit out by bisect is
> after when a4a23f6 was introduced).
Yep. Please continue bisecting the memcpy() oops.
kmemdup() is just a kzalloc() followed by a memcpy(). When we split it
apart by reverting the patch then we would expect the oops to move to
the memcpy() part. Somehow "desc" is a bogus pointer, but I don't
immediately see how that is possible.
regards,
dan carpenter
WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Joseph Salisbury <joseph.salisbury@canonical.com>
Cc: thomas@m3y3r.de, Jiri Kosina <jkosina@suse.cz>,
list@osuosl.org, Haiyang Zhang <haiyangz@microsoft.com>,
LKML <linux-kernel@vger.kernel.org>,
open@osuosl.org, HID CORE LAYER <linux-input@vger.kernel.org>,
devel@linuxdriverproject.org
Subject: Re: [v3.11][Regression] HID: hyperv: convert alloc+memcpy to memdup
Date: Tue, 17 Sep 2013 00:05:04 +0300 [thread overview]
Message-ID: <20130916210503.GQ25896@mwanda> (raw)
In-Reply-To: <52376ED9.5080208@canonical.com>
On Mon, Sep 16, 2013 at 04:49:29PM -0400, Joseph Salisbury wrote:
> On 09/16/2013 04:38 PM, Dan Carpenter wrote:
> > On Mon, Sep 16, 2013 at 01:42:35PM -0400, Joseph Salisbury wrote:
> >> Reverting the patch changes the driver back to useing kzalloc() and
> >> memcpy() instead of kmemdup. Doing so has uncovered another bug, which
> >> causes an oops on memcpy()[1]. We are in the process of bisecting that
> >> one now and will provide the results.
> > The two bugs are the same it's that the code has shifted a little. Mark
> > the commit as buggy and continue with the git bisect.
> >
> > regards,
> > dan carpenter
> Can you explain a little further? Mark commit a4a23f6 as bad? An
> initial bisect already reported that was the first bad commit, so it
> can't be marked bad. The oops on memcpy() happens after commit a4a23f6
> is reverted. The oops on memcpy() did not happen before a4a23f6 was
> committed, so I assume this new oops was introduced by a change later.
>
> Right now I'm bisecting down the oops on memcpy() by updating the bisect
> with good or bad, depending if the test kernel hit the oops. I then
> revert a4a23f6, so that revert is the HEAD of the tree each time before
> building the kernel again(As long as the commit spit out by bisect is
> after when a4a23f6 was introduced).
Yep. Please continue bisecting the memcpy() oops.
kmemdup() is just a kzalloc() followed by a memcpy(). When we split it
apart by reverting the patch then we would expect the oops to move to
the memcpy() part. Somehow "desc" is a bogus pointer, but I don't
immediately see how that is possible.
regards,
dan carpenter
next prev parent reply other threads:[~2013-09-16 21:05 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-16 17:42 [v3.11][Regression] HID: hyperv: convert alloc+memcpy to memdup Joseph Salisbury
2013-09-16 20:38 ` Dan Carpenter
2013-09-16 20:38 ` Dan Carpenter
2013-09-16 20:49 ` Joseph Salisbury
2013-09-16 20:49 ` Joseph Salisbury
2013-09-16 21:05 ` Dan Carpenter [this message]
2013-09-16 21:05 ` Dan Carpenter
2013-09-17 0:44 ` Joseph Salisbury
2013-09-17 0:44 ` Joseph Salisbury
2013-09-24 9:29 ` Jiri Kosina
2013-09-24 13:52 ` Joseph Salisbury
2013-09-24 18:25 ` Joseph Salisbury
2013-09-24 18:25 ` Joseph Salisbury
2013-09-25 17:45 ` Joseph Salisbury
2013-09-27 10:50 ` Jiri Kosina
2013-09-27 10:50 ` Jiri Kosina
2013-09-27 14:42 ` Joseph Salisbury
2013-09-27 14:42 ` Joseph Salisbury
2013-09-27 15:24 ` Dan Carpenter
2013-09-27 15:24 ` Dan Carpenter
2013-09-27 15:59 ` Dan Carpenter
2013-09-30 14:35 ` Jiri Kosina
2013-09-30 14:59 ` Dan Carpenter
2013-09-30 14:59 ` Dan Carpenter
2013-12-16 13:01 ` Jiri Kosina
2013-12-19 9:55 ` David Herrmann
2013-12-19 9:59 ` Jiri Kosina
2013-12-19 10:08 ` David Herrmann
2013-12-19 10:08 ` David Herrmann
2013-12-19 11:22 ` David Herrmann
2013-12-19 11:22 ` David Herrmann
2013-12-19 12:59 ` Jiri Kosina
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=20130916210503.GQ25896@mwanda \
--to=dan.carpenter@oracle.com \
--cc=devel@linuxdriverproject.org \
--cc=haiyangz@microsoft.com \
--cc=jkosina@suse.cz \
--cc=joseph.salisbury@canonical.com \
--cc=linux-input@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=list@osuosl.org \
--cc=open@osuosl.org \
--cc=thomas@m3y3r.de \
/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.