[PATCH] x86/HAP: drop pointless assertions

[PATCH] x86/HAP: drop pointless assertions

[Jan Beulich]

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Just like for shadow code, hap_map_domain_page() is just a thin
wrapper around map_domain_page(), which cannot fail. Asserting its
success is redundant.

hap_unmap_domain_page() should also not be used for something not
mapped through hap_map_domain_page().

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/mm/hap/hap.c
+++ b/xen/arch/x86/mm/hap/hap.c
@@ -233,9 +233,8 @@ static struct page_info *hap_alloc(struc
     d->arch.paging.hap.free_pages--;
 
     p = __map_domain_page(pg);
-    ASSERT(p != NULL);
     clear_page(p);
-    hap_unmap_domain_page(p);
+    unmap_domain_page(p);
 
     return pg;
 }
@@ -375,7 +374,6 @@ static void hap_install_xen_entries_in_l
     l4_pgentry_t *l4e;
 
     l4e = hap_map_domain_page(l4mfn);
-    ASSERT(l4e != NULL);
 
     /* Copy the common Xen mappings from the idle domain */
     memcpy(&l4e[ROOT_PAGETABLE_FIRST_XEN_SLOT],




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x86/HAP: drop pointless assertions

Just like for shadow code, hap_map_domain_page() is just a thin
wrapper around map_domain_page(), which cannot fail. Asserting its
success is redundant.

hap_unmap_domain_page() should also not be used for something not
mapped through hap_map_domain_page().

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/mm/hap/hap.c
+++ b/xen/arch/x86/mm/hap/hap.c
@@ -233,9 +233,8 @@ static struct page_info *hap_alloc(struc
     d->arch.paging.hap.free_pages--;
 
     p = __map_domain_page(pg);
-    ASSERT(p != NULL);
     clear_page(p);
-    hap_unmap_domain_page(p);
+    unmap_domain_page(p);
 
     return pg;
 }
@@ -375,7 +374,6 @@ static void hap_install_xen_entries_in_l
     l4_pgentry_t *l4e;
 
     l4e = hap_map_domain_page(l4mfn);
-    ASSERT(l4e != NULL);
 
     /* Copy the common Xen mappings from the idle domain */
     memcpy(&l4e[ROOT_PAGETABLE_FIRST_XEN_SLOT],

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Re: [PATCH] x86/HAP: drop pointless assertions

[Andrew Cooper]

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On 22/04/14 12:30, Jan Beulich wrote:
> Just like for shadow code, hap_map_domain_page() is just a thin
> wrapper around map_domain_page(), which cannot fail. Asserting its
> success is redundant.
>
> hap_unmap_domain_page() should also not be used for something not
> mapped through hap_map_domain_page().
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

>
> --- a/xen/arch/x86/mm/hap/hap.c
> +++ b/xen/arch/x86/mm/hap/hap.c
> @@ -233,9 +233,8 @@ static struct page_info *hap_alloc(struc
>      d->arch.paging.hap.free_pages--;
>  
>      p = __map_domain_page(pg);
> -    ASSERT(p != NULL);
>      clear_page(p);
> -    hap_unmap_domain_page(p);
> +    unmap_domain_page(p);
>  
>      return pg;
>  }
> @@ -375,7 +374,6 @@ static void hap_install_xen_entries_in_l
>      l4_pgentry_t *l4e;
>  
>      l4e = hap_map_domain_page(l4mfn);
> -    ASSERT(l4e != NULL);
>  
>      /* Copy the common Xen mappings from the idle domain */
>      memcpy(&l4e[ROOT_PAGETABLE_FIRST_XEN_SLOT],
>
>
>
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel


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Re: [PATCH] x86/HAP: drop pointless assertions

[Tim Deegan]

At 12:30 +0100 on 22 Apr (1398166233), Jan Beulich wrote:
> Just like for shadow code, hap_map_domain_page() is just a thin
> wrapper around map_domain_page(), which cannot fail. Asserting its
> success is redundant.
> 
> hap_unmap_domain_page() should also not be used for something not
> mapped through hap_map_domain_page().
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Applied, thanks.

Tim.