linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Linus Torvalds <torvalds@linux-foundation.org>
To: David Rientjes <rientjes@google.com>
Cc: Konrad Rzeszutek Wilk <konrad@kernel.org>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	Dave Jones <davej@redhat.com>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
	Suzuki Poulose <suzuki@in.ibm.com>,
	Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Subject: Re: 3.6rc6 slab corruption.
Date: Wed, 19 Sep 2012 16:01:50 -0700	[thread overview]
Message-ID: <CA+55aFzU1S6cybghVv4Bg2K8X1NC2pX2XebSrEgn0pKtgyCfRw@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1209191438200.21378@chino.kir.corp.google.com>

On Wed, Sep 19, 2012 at 2:49 PM, David Rientjes <rientjes@google.com> wrote:
>
> An alternative to this, though, might be to never test for *ppos == 0 in
> u32_array_read() and do the format_array_alloc() in u32_array_open() to
> initialize file->private_data.  If that allocation fails, just return
> -ENOMEM.  Then you never need to add a mutex in the read path.
>
> Any reason we can't do this?

That does look simpler, and avoiding the lock is a good idea. Since we
don't support lseek() (or pread/pwrite) on that thing anyway, there's
no way to keep the fd open and just re-use it to read the data over
and over, so populating it at open time sounds like a good solution
with no real downsides.

               Linus

  reply	other threads:[~2012-09-19 23:02 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-18 14:35 3.6rc6 slab corruption Dave Jones
2012-09-18 18:38 ` Linus Torvalds
2012-09-18 18:53   ` Dave Jones
2012-09-19 14:00     ` Raghavendra K T
2012-09-19 17:09       ` Linus Torvalds
2012-09-19 21:27         ` David Rientjes
2012-09-19 21:41           ` Dave Jones
2012-09-18 19:23   ` Konrad Rzeszutek Wilk
2012-09-18 20:24     ` David Rientjes
2012-09-18 20:31       ` Konrad Rzeszutek Wilk
2012-09-18 20:36       ` Linus Torvalds
2012-09-19  0:57       ` Raghavendra K T
2012-09-18 20:35     ` Linus Torvalds
2012-09-18 20:37       ` Konrad Rzeszutek Wilk
2012-09-18 20:49         ` Linus Torvalds
2012-09-19  1:16           ` Raghavendra K T
2012-09-19 19:16           ` Konrad Rzeszutek Wilk
2012-09-19 21:29             ` David Rientjes
2012-09-19 21:49               ` David Rientjes
2012-09-19 23:01                 ` Linus Torvalds [this message]
2012-09-19 23:20                   ` David Rientjes
2012-09-20 21:14                     ` Konrad Rzeszutek Wilk
2012-09-20  2:29                 ` Raghavendra K T
2012-09-20  2:46                   ` David Rientjes
2012-09-20  2:55                     ` Raghavendra K T
2012-09-20 21:18                     ` Konrad Rzeszutek Wilk
2012-09-21  9:16                       ` [patch for-3.6] fs, debugfs: fix race in u32_array_read and allocate array at open David Rientjes
2012-09-21 10:22                         ` Raghavendra K T
2012-09-24 22:26                           ` David Rientjes
2012-09-25  2:54                             ` Raghavendra K T
2012-09-20 12:57                 ` 3.6rc6 slab corruption Raghavendra K T
2012-09-20 21:18                   ` Konrad Rzeszutek Wilk
2012-09-20 12:55             ` Raghavendra K T

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=CA+55aFzU1S6cybghVv4Bg2K8X1NC2pX2XebSrEgn0pKtgyCfRw@mail.gmail.com \
    --to=torvalds@linux-foundation.org \
    --cc=davej@redhat.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=konrad.wilk@oracle.com \
    --cc=konrad@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=raghavendra.kt@linux.vnet.ibm.com \
    --cc=rientjes@google.com \
    --cc=suzuki@in.ibm.com \
    --cc=vatsa@linux.vnet.ibm.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;
as well as URLs for NNTP newsgroup(s).