All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>,
	Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-scsi <linux-scsi@vger.kernel.org>
Subject: Re: module: fix module_refcount() return when running in a module exit routine
Date: Fri, 23 Jan 2015 05:17:58 -0800	[thread overview]
Message-ID: <20150123131758.GC8045@infradead.org> (raw)
In-Reply-To: <87iofyurzc.fsf@rustcorp.com.au>

On Fri, Jan 23, 2015 at 01:24:15PM +1030, Rusty Russell wrote:
> The correct fix is to turn try_module_get() into __module_get(), and
> always do the module_put().

Is this really safe?  __module_get sais it needs a non-zero refcount
to start with, but scsi_device_get is the only thing every incrementing
the refcount on the module pointer in the scsi host template, so
exactly that case can happen easily.  There's not assert actually
hardcoding the assumption, so I'm not sure if requirement the comment
really just is nice to have or a strong requirement.

  reply	other threads:[~2015-01-23 13:18 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-18 16:55 module: fix module_refcount() return when running in a module exit routine James Bottomley
2015-01-18 23:37 ` Rusty Russell
2015-01-18 23:37   ` Rusty Russell
2015-01-19  5:18 ` Masami Hiramatsu
2015-01-19  5:51   ` Rusty Russell
2015-01-19  8:28     ` Christoph Hellwig
2015-01-19 16:07       ` James Bottomley
2015-01-19 16:08     ` James Bottomley
2015-01-20  0:45       ` Rusty Russell
2015-01-20  2:17         ` Masami Hiramatsu
2015-01-20 17:23         ` James Bottomley
2015-01-21  5:30           ` Rusty Russell
2015-01-22 16:50           ` Christoph Hellwig
2015-01-22 17:02             ` James Bottomley
2015-01-23  2:54               ` Rusty Russell
2015-01-23 13:17                 ` Christoph Hellwig [this message]
2015-01-23 18:42                   ` James Bottomley
2015-01-23 23:35                     ` Rusty Russell
2015-01-26 17:16                     ` Christoph Hellwig
2015-01-28  9:23                     ` Bart Van Assche
2015-01-28 21:45                       ` James Bottomley
2015-01-29 12:16                         ` Bart Van Assche

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=20150123131758.GC8045@infradead.org \
    --to=hch@infradead.org \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=masami.hiramatsu.pt@hitachi.com \
    --cc=rusty@rustcorp.com.au \
    /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.