diff mbox

[for-next,v3,01/12] x86/mm: make free_perdomain_mappings idempotent

Message ID 20170426155457.10799-2-wei.liu2@citrix.com (mailing list archive)
State New, archived
Headers show

Commit Message

Wei Liu April 26, 2017, 3:54 p.m. UTC 
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
Cc: Tim Deegan <tim@xen.org>
Cc: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
---
 xen/arch/x86/mm.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

George Dunlap April 27, 2017, 10:40 a.m. UTC | #1 
On 26/04/17 16:54, Wei Liu wrote:
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Acked-by: George Dunlap <george.dunlap@citrix.com>

> ---
> Cc: Tim Deegan <tim@xen.org>
> Cc: George Dunlap <george.dunlap@eu.citrix.com>
> Cc: Jan Beulich <jbeulich@suse.com>
> Cc: Andrew Cooper <andrew.cooper3@citrix.com>
> ---
>  xen/arch/x86/mm.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
> index bd68e56dc7..cdef5c49c4 100644
> --- a/xen/arch/x86/mm.c
> +++ b/xen/arch/x86/mm.c
> @@ -6503,9 +6503,14 @@ void destroy_perdomain_mapping(struct domain *d, unsigned long va,
>  
>  void free_perdomain_mappings(struct domain *d)
>  {
> -    l3_pgentry_t *l3tab = __map_domain_page(d->arch.perdomain_l3_pg);
> +    l3_pgentry_t *l3tab;
>      unsigned int i;
>  
> +    if ( !d->arch.perdomain_l3_pg )
> +        return;
> +
> +    l3tab = __map_domain_page(d->arch.perdomain_l3_pg);
> +
>      for ( i = 0; i < PERDOMAIN_SLOTS; ++i)
>          if ( l3e_get_flags(l3tab[i]) & _PAGE_PRESENT )
>          {
> @@ -6544,6 +6549,7 @@ void free_perdomain_mappings(struct domain *d)
>  
>      unmap_domain_page(l3tab);
>      free_domheap_page(d->arch.perdomain_l3_pg);
> +    d->arch.perdomain_l3_pg = NULL;
>  }
>  
>  #ifdef MEMORY_GUARD
>
diff mbox

Patch

diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
index bd68e56dc7..cdef5c49c4 100644
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -6503,9 +6503,14 @@  void destroy_perdomain_mapping(struct domain *d, unsigned long va,
 
 void free_perdomain_mappings(struct domain *d)
 {
-    l3_pgentry_t *l3tab = __map_domain_page(d->arch.perdomain_l3_pg);
+    l3_pgentry_t *l3tab;
     unsigned int i;
 
+    if ( !d->arch.perdomain_l3_pg )
+        return;
+
+    l3tab = __map_domain_page(d->arch.perdomain_l3_pg);
+
     for ( i = 0; i < PERDOMAIN_SLOTS; ++i)
         if ( l3e_get_flags(l3tab[i]) & _PAGE_PRESENT )
         {
@@ -6544,6 +6549,7 @@  void free_perdomain_mappings(struct domain *d)
 
     unmap_domain_page(l3tab);
     free_domheap_page(d->arch.perdomain_l3_pg);
+    d->arch.perdomain_l3_pg = NULL;
 }
 
 #ifdef MEMORY_GUARD