Re: [PATCH v3] EFI/runtime: switch to xv[mz]alloc_array()

[dmkhn@xxxxxxxxx]

On Wed, Jul 23, 2025 at 03:39:11PM +0200, Jan Beulich wrote:
> Use the more "modern" form, thus doing away with effectively open-coding
> xmalloc_array() at the same time. While there is a difference in
> generated code, as xmalloc_bytes() forces SMP_CACHE_BYTES alignment, if
> code really cared about such higher than default alignment, it should
> request so explicitly.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Denis Mukhin <dmukhin@xxxxxxxx> 

> ---
> v3: Use xv[mz]alloc_array().
> 
> --- a/xen/common/efi/runtime.c
> +++ b/xen/common/efi/runtime.c
> @@ -6,6 +6,7 @@
>  #include <xen/irq.h>
>  #include <xen/sections.h>
>  #include <xen/time.h>
> +#include <xen/xvmalloc.h>
> 
>  DEFINE_XEN_GUEST_HANDLE(CHAR16);
> 
> @@ -500,23 +501,23 @@ int efi_runtime_call(struct xenpf_efi_ru
>          len = gwstrlen(guest_handle_cast(op->u.get_variable.name, CHAR16));
>          if ( len < 0 )
>              return len;
> -        name = xmalloc_array(CHAR16, ++len);
> +        name = xvmalloc_array(CHAR16, ++len);
>          if ( !name )
>             return -ENOMEM;
>          if ( __copy_from_guest(name, op->u.get_variable.name, len) ||
>               wmemchr(name, 0, len) != name + len - 1 )
>          {
> -            xfree(name);
> +            xvfree(name);
>              return -EIO;
>          }
> 
>          size = op->u.get_variable.size;
>          if ( size )
>          {
> -            data = xmalloc_bytes(size);
> +            data = xvmalloc_array(unsigned char, size);
>              if ( !data )
>              {
> -                xfree(name);
> +                xvfree(name);
>                  return -ENOMEM;
>              }
>          }
> @@ -539,8 +540,8 @@ int efi_runtime_call(struct xenpf_efi_ru
>          else
>              rc = -EOPNOTSUPP;
> 
> -        xfree(data);
> -        xfree(name);
> +        xvfree(data);
> +        xvfree(name);
>      }
>      break;
> 
> @@ -553,17 +554,17 @@ int efi_runtime_call(struct xenpf_efi_ru
>          len = gwstrlen(guest_handle_cast(op->u.set_variable.name, CHAR16));
>          if ( len < 0 )
>              return len;
> -        name = xmalloc_array(CHAR16, ++len);
> +        name = xvmalloc_array(CHAR16, ++len);
>          if ( !name )
>             return -ENOMEM;
>          if ( __copy_from_guest(name, op->u.set_variable.name, len) ||
>               wmemchr(name, 0, len) != name + len - 1 )
>          {
> -            xfree(name);
> +            xvfree(name);
>              return -EIO;
>          }
> 
> -        data = xmalloc_bytes(op->u.set_variable.size);
> +        data = xvmalloc_array(unsigned char, op->u.set_variable.size);
>          if ( !data )
>              rc = -ENOMEM;
>          else if ( copy_from_guest(data, op->u.set_variable.data,
> @@ -581,8 +582,8 @@ int efi_runtime_call(struct xenpf_efi_ru
>              efi_rs_leave(&state);
>          }
> 
> -        xfree(data);
> -        xfree(name);
> +        xvfree(data);
> +        xvfree(name);
>      }
>      break;
> 
> @@ -598,13 +599,13 @@ int efi_runtime_call(struct xenpf_efi_ru
>              return -EINVAL;
> 
>          size = op->u.get_next_variable_name.size;
> -        name.raw = xzalloc_bytes(size);
> +        name.raw = xvzalloc_array(unsigned char, size);
>          if ( !name.raw )
>              return -ENOMEM;
>          if ( copy_from_guest(name.raw, op->u.get_next_variable_name.name,
>                               size) )
>          {
> -            xfree(name.raw);
> +            xvfree(name.raw);
>              return -EFAULT;
>          }
> 
> @@ -629,7 +630,7 @@ int efi_runtime_call(struct xenpf_efi_ru
>          else
>              rc = -EOPNOTSUPP;
> 
> -        xfree(name.raw);
> +        xvfree(name.raw);
>      }
>      break;
> 
>