linux-kernel - Re: [PATCH] virtio_blk: allow re-reading config space at runtime

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20110201183827.GB24924@redhat.com>
Date:	Tue, 1 Feb 2011 20:38:27 +0200
From:	"Michael S. Tsirkin" <mst@...hat.com>
To:	Christoph Hellwig <hch@....de>
Cc:	Rusty Russell <rusty@...tcorp.com.au>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] virtio_blk: allow re-reading config space at runtime

On Tue, Feb 01, 2011 at 06:32:34PM +0100, Christoph Hellwig wrote:
> On Thu, Jan 27, 2011 at 05:29:26PM +0200, Michael S. Tsirkin wrote:
> > Yes but in that specific situation (double schedule before
> > it runs once) discarding one change notification
> > would not hurt at all.
> 
> Except that you can't easily do it.  We can't simply reuse a work
> structure embedded in say struct virtio_blk without first doing a
> flush_work_sync/cancel_work_sync to remove it from the internal
> workqueue.c queues.
>  And those calls can sleep and thus can't be called
> from interrupt context either.

Should not be hard to solve.
If it's running, it is ok to requeue.  I don't remember offhand if it's
ok to requeue if it's queued but not running, if not we could have a
flag that signals that's the case.

--
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/