Re: [PATCH v10 03/13] x86/mm: switch to new APIs in modify_xen_mappings

[Hongyan Xia <hx242@xxxxxxx>]

On Wed, 2021-04-21 at 15:15 +0100, Hongyan Xia wrote:
> From: Wei Liu <wei.liu2@xxxxxxxxxx>
> 
> Page tables allocated in that function should be mapped and unmapped
> now.
> 
> Note that pl2e now maybe mapped and unmapped in different iterations,
> so
> we need to add clean-ups for that.
> 
> Signed-off-by: Wei Liu <wei.liu2@xxxxxxxxxx>
> Signed-off-by: Hongyan Xia <hongyxia@xxxxxxxxxx>
> Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
> 
> ---
> Changed in v7:
> - use normal unmap in the error path.
> ---
>  xen/arch/x86/mm.c | 57 ++++++++++++++++++++++++++++++---------------
> --
>  1 file changed, 36 insertions(+), 21 deletions(-)
> 
> diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
> index 8a68da26f45f..832e654294b4 100644
> --- a/xen/arch/x86/mm.c
> +++ b/xen/arch/x86/mm.c
> @@ -5546,6 +5546,7 @@ int map_pages_to_xen(
>  
>   out:
>      L3T_UNLOCK(current_l3page);
> +    unmap_domain_page(pl2e);
>      unmap_domain_page(pl3e);
>      unmap_domain_page(pl2e);
>      return rc;

Something is seriously wrong here. This is obviously a mis-hunk which
should have been at the end of modify_xen_mappings() instead of
map_pages_to_xen(). This time the context is also different so I don't
understand why it did not conflict when I rebased.

Apologies. I noticed this patch has been merged so I will send a fix
right away.

Hongyan