linux-kernel - Re: [PATCH] NLM: Add lockd reference counting and clean up lockd startup and shutdown

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 13 Dec 2007 09:40:09 -0500
From:	Jeff Layton <jlayton@...hat.com>
To:	Christoph Hellwig <hch@...radead.org>
Cc:	linux-nfs@...r.kernel.org, nfsv4@...ux-nfs.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] NLM: Add lockd reference counting and clean up lockd
 startup and shutdown

On Sat, 8 Dec 2007 14:07:47 +0000
Christoph Hellwig <hch@...radead.org> wrote:

> > +	mutex_lock(&nlmsvc_mutex);
> > +	while (atomic_read(&nlmsvc_ref) != 0) {
> 
> might be better to do the refcounting outside the thread and use the
> kthread api, which is something we still need to do for lockd anyway.
> 

I took a swipe at doing this, and have a set of patches that make lockd
use kthreads. It works well, but there's a problem once I add in the
reference counting.

In the situation that prompted this whole thing, the last nlmsvc_ref
gets put by lockd itself. A kthread can't call kthread_stop on itself
since it will deadlock.

Is there a way to gracefully allow a kthread to shut itself down?
Alternately, I suppose I could schedule_work() the kthread_stop, though
that seems sort of ugly...

-- 
Jeff Layton <jlayton@...hat.com>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/