Re: [kvm-unit-tests PATCH 4/6] s390x: Test for share/unshare call support before using them

[Claudio Imbrenda <imbrenda@linux.ibm.com>]

On Tue, 16 Mar 2021 09:16:52 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> Testing for facility only means the UV Call facility is available.
> The UV will only indicate the share/unshare calls for a protected
> guest 2, so let's also check that.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
>  lib/s390x/malloc_io.c | 5 +++--
>  s390x/uv-guest.c      | 6 ++++++
>  2 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/s390x/malloc_io.c b/lib/s390x/malloc_io.c
> index 1dcf1691..78582eac 100644
> --- a/lib/s390x/malloc_io.c
> +++ b/lib/s390x/malloc_io.c
> @@ -19,6 +19,7 @@
>  #include <alloc_page.h>
>  #include <asm/facility.h>
>  #include <bitops.h>
> +#include <uv.h>
>  
>  static int share_pages(void *p, int count)
>  {
> @@ -47,7 +48,7 @@ void *alloc_io_mem(int size, int flags)
>  	assert(size);
>  
>  	p = alloc_pages_flags(order, AREA_DMA31 | flags);
> -	if (!p || !test_facility(158))
> +	if (!p || !uv_os_is_guest())
>  		return p;
>  
>  	n = share_pages(p, 1 << order);
> @@ -65,7 +66,7 @@ void free_io_mem(void *p, int size)
>  
>  	assert(IS_ALIGNED((uintptr_t)p, PAGE_SIZE));
>  
> -	if (test_facility(158))
> +	if (uv_os_is_guest())
>  		unshare_pages(p, 1 << order);
>  	free_pages(p);
>  }
> diff --git a/s390x/uv-guest.c b/s390x/uv-guest.c
> index 95a968c5..8915b2f1 100644
> --- a/s390x/uv-guest.c
> +++ b/s390x/uv-guest.c
> @@ -16,6 +16,7 @@
>  #include <asm/facility.h>
>  #include <asm/uv.h>
>  #include <sclp.h>
> +#include <uv.h>
>  
>  static unsigned long page;
>  
> @@ -141,6 +142,11 @@ int main(void)
>  		goto done;
>  	}
>  
> +	if (!uv_os_is_guest()) {
> +		report_skip("Not a protected guest");
> +		goto done;
> +	}
> +
>  	page = (unsigned long)alloc_page();
>  	test_priv();
>  	test_invalid();