linux-block.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Greg KH <gregkh@linuxfoundation.org>
To: Luis Chamberlain <mcgrof@kernel.org>
Cc: minchan@kernel.org, jeyu@kernel.org, ngupta@vflare.org,
	sergey.senozhatsky.work@gmail.com, axboe@kernel.dk,
	mbenes@suse.com, jpoimboe@redhat.com, tglx@linutronix.de,
	keescook@chromium.org, jikos@kernel.org, rostedt@goodmis.org,
	peterz@infradead.org, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 2/3] zram: fix deadlock with sysfs attribute usage and driver removal
Date: Tue, 22 Jun 2021 09:41:23 +0200	[thread overview]
Message-ID: <YNGUIzh7aR3C/Hoz@kroah.com> (raw)
In-Reply-To: <20210621233634.595649-1-mcgrof@kernel.org>

On Mon, Jun 21, 2021 at 04:36:34PM -0700, Luis Chamberlain wrote:
> +	ssize_t __ret; \
> +	if (!try_module_get(THIS_MODULE)) \

try_module_get(THIS_MODULE) is always racy and probably does not do what
you want it to do.  You always want to get/put module references from
code that is NOT the code calling these functions.

> +		return -ENODEV; \
> +	__ret = _name ## _store(dev, attr, buf, len); \
> +	module_put(THIS_MODULE); \

This too is going to be racy.

While fun to poke at, I still think this is pointless.

greg k-h

  reply	other threads:[~2021-06-22  7:41 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-21 23:30 [PATCH v3 0/3] zram: fix few sysfs races Luis Chamberlain
2021-06-21 23:30 ` [PATCH v3 1/3] zram: fix crashes due to use of cpu hotplug multistate Luis Chamberlain
2021-06-22  7:39   ` Greg KH
2021-06-22 15:12     ` Luis Chamberlain
2021-06-21 23:36 ` [PATCH v3 2/3] zram: fix deadlock with sysfs attribute usage and driver removal Luis Chamberlain
2021-06-22  7:41   ` Greg KH [this message]
2021-06-22 15:27     ` Luis Chamberlain
2021-06-22 16:27       ` Greg KH
2021-06-22 16:40         ` Luis Chamberlain
2021-06-22 16:51           ` Greg KH
2021-06-22 17:00             ` Luis Chamberlain
2021-06-22  7:45   ` Greg KH
2021-06-22 16:32     ` Luis Chamberlain
2021-06-22 17:16       ` Greg KH
2021-06-22 17:27         ` Luis Chamberlain
2021-06-22 18:05           ` Greg KH
2021-06-22 19:57             ` Luis Chamberlain
2021-06-21 23:36 ` [PATCH v3 3/3] drivers/base/core: refcount kobject and bus on device attribute read / store Luis Chamberlain
2021-06-22  7:46   ` Greg KH
2021-06-22 16:44     ` Luis Chamberlain
2021-06-22 16:48       ` 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=YNGUIzh7aR3C/Hoz@kroah.com \
    --to=gregkh@linuxfoundation.org \
    --cc=axboe@kernel.dk \
    --cc=jeyu@kernel.org \
    --cc=jikos@kernel.org \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mbenes@suse.com \
    --cc=mcgrof@kernel.org \
    --cc=minchan@kernel.org \
    --cc=ngupta@vflare.org \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=sergey.senozhatsky.work@gmail.com \
    --cc=tglx@linutronix.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 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).