Re: [PATCH] x86/shadow: fix uninitialized rc shadow_track_dirty_vram()

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 22/05/2015 07:29, Jan Beulich wrote:
> Commit bd1b4a71b3 ("x86/shadow: fix shadow_track_dirty_vram to work on
> hvm guests"), trying to mirror its HAP counterpart, deleted a couple of
> assignments to rc without making sure rc is initialized on all paths.
>
> Coverity ID: 1299410
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

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

>
> --- a/xen/arch/x86/mm/shadow/common.c
> +++ b/xen/arch/x86/mm/shadow/common.c
> @@ -3518,7 +3518,7 @@ int shadow_track_dirty_vram(struct domain
>                              unsigned long nr,
>                              XEN_GUEST_HANDLE_64(uint8) guest_dirty_bitmap)
>  {
> -    int rc;
> +    int rc = 0;
>      unsigned long end_pfn = begin_pfn + nr;
>      unsigned long dirty_size = (nr + 7) / 8;
>      int flush_tlb = 0;
> @@ -3550,10 +3550,7 @@ int shadow_track_dirty_vram(struct domain
>      }
>  
>      if ( !nr )
> -    {
> -        rc = 0;
>          goto out;
> -    }
>  
>      dirty_bitmap = vzalloc(dirty_size);
>      if ( dirty_bitmap == NULL )
>
>
>