Prev: [PATCH 0/3] vhost: logging fixes
Next: [PATCH] scripts/get_maintainer.pl: Fix possible infinite loop
From: Juan Quintela on 23 Feb 2010 15:00
"Michael S. Tsirkin" <mst(a)redhat.com> wrote:
> get_user_pages_fast returns number of pages on success, negative value
> on failure, but never 0. Fix vhost code to match this logic.

It can return 0 if you ask for 0 pages :)
From the comment:

* Returns number of pages pinned. This may be fewer than the number
* requested. If nr_pages is 0 or negative, returns 0. If no pages
* were pinned, returns -errno.
*/

I agree that code was wrong, but the BUG_ON() is not neccessary
IMHO. The important bit is the change in the comparison.

Reviewed-by: Juan Quintela <quintela(a)redhat.com>


> Signed-off-by: Michael S. Tsirkin <mst(a)redhat.com>
> ---
> drivers/vhost/vhost.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index d4f8fdf..d003504 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -646,8 +646,9 @@ static int set_bit_to_user(int nr, void __user *addr)
> int bit = nr + (log % PAGE_SIZE) * 8;
> int r;
> r = get_user_pages_fast(log, 1, 1, &page);
> - if (r)
> + if (r < 0)
> return r;
> + BUG_ON(r != 1);
> base = kmap_atomic(page, KM_USER0);
> set_bit(bit, base);
> kunmap_atomic(base, KM_USER0);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
From: David Miller on 23 Feb 2010 17:50

Just for the record I'm generally not interested in vhost
patches.

If it's a specific network one that will be merged via
the networking tree, yes please CC: me.

But if it's a bunch of changes to vhost.c and other pieces
of infrastructure, feel free to leave me out of it. It just
clutters my already overflowing inbox.

Thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
From: Michael S. Tsirkin on 24 Feb 2010 00:50
On Tue, Feb 23, 2010 at 02:42:35PM -0800, David Miller wrote:
>
> Just for the record I'm generally not interested in vhost
> patches.
>
> If it's a specific network one that will be merged via
> the networking tree, yes please CC: me.
>
> But if it's a bunch of changes to vhost.c and other pieces
> of infrastructure, feel free to leave me out of it. It just
> clutters my already overflowing inbox.
>
> Thanks.

Dave, so while Rusty's on vacation, what's the best way to get vhost
infrastructure fixes in? Are you ok with getting pull requests and
merging them into net-next? That should keep the clutter in your inbox
to the minimum.

Of course network changes would still go the usual way.

--
MST
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
From: David Miller on 24 Feb 2010 02:10
From: "Michael S. Tsirkin" <mst(a)redhat.com>
Date: Wed, 24 Feb 2010 07:37:37 +0200

> Dave, so while Rusty's on vacation, what's the best way to get vhost
> infrastructure fixes in? Are you ok with getting pull requests and
> merging them into net-next? That should keep the clutter in your inbox
> to the minimum.
>
> Of course network changes would still go the usual way.

Well, who is providing oversight of vhost work while he's
gone? Has he, implicitly or explicitly, appointed a maintainer
while he's away?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
From: Michael S. Tsirkin on 24 Feb 2010 02:50
On Tue, Feb 23, 2010 at 11:04:28PM -0800, David Miller wrote:
> From: "Michael S. Tsirkin" <mst(a)redhat.com>
> Date: Wed, 24 Feb 2010 07:37:37 +0200
>
> > Dave, so while Rusty's on vacation, what's the best way to get vhost
> > infrastructure fixes in? Are you ok with getting pull requests and
> > merging them into net-next? That should keep the clutter in your inbox
> > to the minimum.
> >
> > Of course network changes would still go the usual way.
>
> Well, who is providing oversight of vhost work while he's
> gone?

My plan was to get peer review of the patches before merging.
So far Juan Quintela and Gleb Natapov gave feedback.

> Has he, implicitly or explicitly, appointed a maintainer
> while he's away?

Implicitly, I guess. He said "if there's an issue Michael Tsirkin is the
best person to resolve it", this was wrt merging his virtio&lguest tree.
He didn't mention vhost, I wrote all of vhost though, there shouldn't be
an issue with that.

--
MST
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
First  |  Prev  |  Next  |  Last
Pages: 1 2 3
Prev: [PATCH 0/3] vhost: logging fixes
Next: [PATCH] scripts/get_maintainer.pl: Fix possible infinite loop