Re: [PATCH] xen/gntdev: do not set VM_PFNMAP

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Tue, 3 Apr 2012, Konrad Rzeszutek Wilk wrote:
> On Tue, Apr 03, 2012 at 12:25:02PM +0100, Stefano Stabellini wrote:
> > Since when we are using the m2p_override it is not true anymore that the
>         ^^^^ - get rid of that.
> > mmap'ed area doesn't have corresponsing struct pages.
> 
> That reads to me as !!do struct page. Which comes out as:
> 
> "m2p_override_* API the mmap-ed are have corresponding struct pages' ?

Yes, indeed: m2p_override_* provides the corresponding struct pages


> > Removing the VM_PFNMAP flag makes get_user_pages work on the mmap'ed user vma.
> > An example test case would be using a Xen userspace block backend
> > (QDISK) on a file on NFS using O_DIRECT.
> > 
> > The patch should be backported back to 2.6.38.
> 
> Add CC: stable@kernel.org then.

I'll resend CCing stable


> But does this patch depend on other
> patches?

only on the m2p_override, that is in Linux since 2.6.38