Re: [stable] [PATCH] cifs: fix wsize negotiation for 2.6.39 stable

[Jeff Layton <jlayton@redhat.com>]

On Wed, 13 Jul 2011 04:26:19 +0200
Greg KH <greg@kroah.com> wrote:

> On Tue, Jul 12, 2011 at 09:24:41PM -0400, Jeff Layton wrote:
> > I sent this a week or so ago, but it apparently missed the recent
> > 2.6.39.y release. Resending to make sure it gets into the next one.
> > 
> > Prior to 2.6.39, when signing was enabled on a socket the client only
> > sent single-page writes. This changed with commit ca83ce3d5b, which
> > made signed and unsigned connections use the same codepaths for write
> > calls.
> > 
> > This caused a regression when working with windows servers. Windows
> > machines will reject writes larger than the MaxBufferSize when signing
> > is active, but does not clear the CAP_LARGE_WRITE_X flag in the
> > negotiation.
> > 
> > This patch backports 2 patches that fix this problem in 3.0 kernels,
> > and changes a couple of the constants to values appropriate for the
> > writeback code in 2.6.39.
> 
> Why not just tell me the 2 patches in upstream that need to be
> backported as Documentation/stable_kernel_rules.txt say to do instead?
> 
> thanks,
> 
> greg k-h

Ok, we can do it that way instead. I just sent a patch to
stable@kernel.org that alters the constants after listing the upstream
patches as prerequisites.

Unfortunately, we cannot simply cherry-pick the upstream patches to fix
this. 3.0 added support for much larger wsize= values in cifs, and we
have to account for that difference in 2.6.39.y.

Thanks,
-- 
Jeff Layton <jlayton@redhat.com>