linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Mike Snitzer <snitzer@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>,
	axboe@kernel.dk, hch@lst.de, James.Bottomley@suse.de,
	linux-scsi@vger.kernel.org, dm-devel@redhat.com,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] scsi: address leak in the error path of discard page allocation
Date: Fri, 2 Jul 2010 12:48:24 +0200	[thread overview]
Message-ID: <20100702104824.GB26318@lst.de> (raw)
In-Reply-To: <20100701130328.GB19605@redhat.com>

On Thu, Jul 01, 2010 at 09:03:28AM -0400, Mike Snitzer wrote:
> On Thu, Jul 01 2010 at  6:49am -0400,
> FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> wrote:
> 
> > This fixes discard page leak by using q->unprep_rq_fn facility.
> > 
> > q->unprep_rq_fn is called when all the data buffer (req->bio and
> > scsi_data_buffer) in the request is freed.
> > 
> > sd_unprep() uses rq->buffer to free discard page allocated in
> > sd_prepare_discard().
> > 
> > Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> 
> Thanks for sorting this out Tomo, all 3 patches work great!
> 
> BTW, there is one remaining (rare) leak in the allocation path.
> 
> The following patch serves to fix it but I'm not sure if there is a more
> elegant way to address this.
> 
> An alternative would be to check if the page is already allocated
> (before allocating the page in scsi_setup_discard_cmnd)?

Ah, should have read your mail first, sorry..


  parent reply	other threads:[~2010-07-02 10:48 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-01 10:49 FUJITA Tomonori
2010-07-01 10:49 ` [PATCH 1/3] block: implement an unprep function corresponding directly to prep FUJITA Tomonori
2010-07-01 13:30   ` James Bottomley
2010-07-01 10:49 ` [PATCH 2/3] scsi: add sd_unprep_fn to free discard page FUJITA Tomonori
2010-07-01 13:03   ` [PATCH] scsi: address leak in the error path of discard page allocation Mike Snitzer
2010-07-01 20:15     ` Mike Snitzer
2010-07-01 20:19       ` James Bottomley
2010-07-01 21:07         ` Mike Snitzer
2010-07-02 10:49           ` Christoph Hellwig
2010-07-02  4:53         ` FUJITA Tomonori
2010-07-02 10:52           ` Christoph Hellwig
2010-07-02 13:08             ` Mike Snitzer
2010-07-05  4:00               ` FUJITA Tomonori
2010-07-02 10:48     ` Christoph Hellwig [this message]
2010-07-02 10:48   ` [PATCH 2/3] scsi: add sd_unprep_fn to free discard page Christoph Hellwig
2010-07-05 10:07   ` Boaz Harrosh
2010-07-01 10:49 ` [PATCH 3/3] scsi: remove unused free discard page in sd_done FUJITA Tomonori
2010-07-02 10:52   ` Christoph Hellwig
2010-07-01 12:29 ` Jens Axboe
2010-07-01 13:40 ` add sd_unprep_fn to free discard page Boaz Harrosh
2010-07-01 13:57   ` James Bottomley

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=20100702104824.GB26318@lst.de \
    --to=hch@lst.de \
    --cc=James.Bottomley@suse.de \
    --cc=axboe@kernel.dk \
    --cc=dm-devel@redhat.com \
    --cc=fujita.tomonori@lab.ntt.co.jp \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=snitzer@redhat.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).