Re: [PATCH] xen/gnttab: leave lazy MMU mode in the case of a m2p override failure

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

On Fri, 22 Nov 2013, Konrad Rzeszutek Wilk wrote:
> On Wed, Nov 20, 2013 at 12:11:35PM -0800, Matt Wilson wrote:
> > From: Matt Wilson <msw@amazon.com>
> > 
> > Commit f62805f1 introduced a bug where lazy MMU mode isn't exited if a
> > m2p_add/remove_override call fails.
> 
> Stefano?
> 

Already acked here:

http://marc.info/?l=linux-kernel&m=138505917602905&w=2



> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> > Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> > Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> > Cc: David Vrabel <david.vrabel@citrix.com>
> > Cc: Anthony Liguori <aliguori@amazon.com>
> > Cc: xen-devel@lists.xenproject.org
> > Cc: linux-kernel@vger.kernel.org
> > Signed-off-by: Matt Wilson <msw@amazon.com>
> > ---
> >  drivers/xen/grant-table.c |    6 ++++--
> >  1 file changed, 4 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
> > index 62ccf54..0283871 100644
> > --- a/drivers/xen/grant-table.c
> > +++ b/drivers/xen/grant-table.c
> > @@ -930,9 +930,10 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
> >  		ret = m2p_add_override(mfn, pages[i], kmap_ops ?
> >  				       &kmap_ops[i] : NULL);
> >  		if (ret)
> > -			return ret;
> > +			goto out;
> >  	}
> >  
> > + out:
> >  	if (lazy)
> >  		arch_leave_lazy_mmu_mode();
> >  
> > @@ -969,9 +970,10 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
> >  		ret = m2p_remove_override(pages[i], kmap_ops ?
> >  				       &kmap_ops[i] : NULL);
> >  		if (ret)
> > -			return ret;
> > +			goto out;
> >  	}
> >  
> > + out:
> >  	if (lazy)
> >  		arch_leave_lazy_mmu_mode();
> >  
> > -- 
> > 1.7.9.5
> > 
>