From: Tejun Heo <tj@kernel.org>
To: Petr Mladek <pmladek@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Josh Triplett <josh@joshtriplett.org>,
Thomas Gleixner <tglx@linutronix.de>,
Linus Torvalds <torvalds@linux-foundation.org>,
Jiri Kosina <jkosina@suse.cz>, Borislav Petkov <bp@suse.de>,
Michal Hocko <mhocko@suse.cz>,
linux-mm@kvack.org, Vlastimil Babka <vbabka@suse.cz>,
linux-api@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v9 06/12] kthread: Add kthread_drain_worker()
Date: Wed, 29 Jun 2016 09:15:52 -0400 [thread overview]
Message-ID: <20160629131552.GA24054@htj.duckdns.org> (raw)
In-Reply-To: <20160629081748.GA3238@pathway.suse.cz>
Hello,
On Wed, Jun 29, 2016 at 10:17:48AM +0200, Petr Mladek wrote:
> > Ah, okay, I don't think we need to change this. I was suggesting to
> > simplify it by dropping the draining and just do flush from destroy.
>
> I see. But then it does not address the original concern from Peter
> Zijlstra. He did not like that the caller was responsible for blocking
> further queueing. It still will be needed. Or did I miss something,
> please?
You can only protect against so much. Let's say we make the worker
struct to be allocated by the user, what then prevents it prematurely
from user side? Use-after-free is use-after-free. If we can trivally
add some protection against it, great, but no need to contort the
design to add marginal protection.
Thanks.
--
tejun
next prev parent reply other threads:[~2016-06-29 13:16 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-16 11:17 [PATCH v9 00/12] kthread: Kthread worker API improvements Petr Mladek
2016-06-16 11:17 ` [PATCH v9 01/12] kthread: Rename probe_kthread_data() to kthread_probe_data() Petr Mladek
2016-06-20 19:16 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 02/12] kthread: Kthread worker API cleanup Petr Mladek
2016-06-20 19:27 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 03/12] kthread/smpboot: Do not park in kthread_create_on_cpu() Petr Mladek
2016-06-16 11:17 ` [PATCH v9 04/12] kthread: Allow to call __kthread_create_on_node() with va_list args Petr Mladek
2016-06-20 19:51 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 05/12] kthread: Add kthread_create_worker*() Petr Mladek
2016-06-20 19:55 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 06/12] kthread: Add kthread_drain_worker() Petr Mladek
2016-06-20 19:56 ` Tejun Heo
2016-06-22 20:54 ` Peter Zijlstra
2016-06-23 21:32 ` Tejun Heo
2016-06-24 7:05 ` Peter Zijlstra
2016-06-24 9:08 ` Petr Mladek
2016-06-24 15:54 ` Tejun Heo
2016-06-27 14:33 ` Petr Mladek
2016-06-28 17:04 ` Tejun Heo
2016-06-29 8:17 ` Petr Mladek
2016-06-29 13:15 ` Tejun Heo [this message]
2016-06-16 11:17 ` [PATCH v9 07/12] kthread: Add kthread_destroy_worker() Petr Mladek
2016-06-20 19:57 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 08/12] kthread: Detect when a kthread work is used by more workers Petr Mladek
2016-06-20 20:10 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 09/12] kthread: Initial support for delayed kthread work Petr Mladek
2016-06-20 20:20 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 10/12] kthread: Allow to cancel " Petr Mladek
2016-06-20 20:27 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 11/12] kthread: Allow to modify delayed " Petr Mladek
2016-06-20 20:29 ` Tejun Heo
2016-06-16 11:17 ` [PATCH v9 12/12] kthread: Better support freezable kthread workers Petr Mladek
2016-06-20 20:30 ` Tejun Heo
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=20160629131552.GA24054@htj.duckdns.org \
--to=tj@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=bp@suse.de \
--cc=jkosina@suse.cz \
--cc=josh@joshtriplett.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.cz \
--cc=mingo@redhat.com \
--cc=oleg@redhat.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=vbabka@suse.cz \
/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).