From: Greg KH <gregkh@linuxfoundation.org>
To: Chuansheng Liu <chuansheng.liu@intel.com>
Cc: dmitry.torokhov@gmail.com, tj@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] devres: Freeing the drs after all release() are called
Date: Wed, 6 Nov 2013 00:58:59 -0800 [thread overview]
Message-ID: <20131106085859.GB9487@kroah.com> (raw)
In-Reply-To: <1383720018.3650.37.camel@cliu38-desktop-build>
On Wed, Nov 06, 2013 at 02:40:18PM +0800, Chuansheng Liu wrote:
>
> In release_nodes(), it will call dr->node.release() and kfree
> dr one by one.
>
> But sometimes the previous dr maybe be used by next .release(),
> such as:
> [50314.855534] [<c12b172f>] ? synchronize_irq+0x3f/0xb0
> [50314.861193] [<c12b18e9>] __free_irq+0x149/0x200
> [50314.866367] [<c12b19e3>] free_irq+0x43/0xa0
> [50314.871152] [<c12b4864>] devm_irq_release+0x14/0x20
> [50314.876713] [<c169e806>] release_nodes+0x136/0x1b0
> [50314.882178] [<c169ee79>] devres_release_all+0x39/0x60
> [50314.887935] [<c169b411>] __device_release_driver+0x71/0xd0
>
> the free_irq() will sync the last irq handling, which maybe use
> freed dr, then it will cause memory corruption.
>
> Here split the dr kfreeing actions after all dr->node.release().
But you aren't really solving any problems here, how is dr being used
after the release function is called? Who is doing it in such a way
that this change would really fix anything?
thanks,
greg k-h
next prev parent reply other threads:[~2013-11-06 8:56 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-06 6:40 [PATCH] devres: Freeing the drs after all release() are called Chuansheng Liu
2013-11-06 8:58 ` Greg KH [this message]
2013-11-07 0:27 ` Liu, Chuansheng
2013-11-07 0:29 ` tj
2013-11-07 0:36 ` Liu, Chuansheng
2013-11-07 0:46 ` Dmitry Torokhov
2013-11-07 0:53 ` Liu, Chuansheng
2013-11-07 0:51 ` tj
2013-11-07 1:18 ` Liu, Chuansheng
2013-11-07 1:56 ` Greg KH
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=20131106085859.GB9487@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=chuansheng.liu@intel.com \
--cc=dmitry.torokhov@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@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