Re: [PATCH v9 5/5] x86/pvh: fix unbootable VMs by really inlining memset() in xen_prepare_pvh()

[Borislav Petkov <bp@xxxxxxxxx>]

On Sat, Aug 22, 2026 at 03:33:21PM -0300, Mauricio Faria de Oliveira wrote:
> Even with __builtin the compiler may decide to use the out of line function
> instead of the inline implementation.
> 
> This particular one (still) generated the inline implementation as expected
> (at least in these compiler versions) but this is not guaranteed to remain.
> 
> Switch the builtin to the inline implementation to address it.
> 
> Fixes: fbe5a6dfe492 ("xen, pvh: fix unbootable VMs by inlining memset() in 
> xen_prepare_pvh()")
> Signed-off-by: Mauricio Faria de Oliveira <mfo@xxxxxxxxxx>
> Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
> ---
>  arch/x86/platform/pvh/enlighten.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/platform/pvh/enlighten.c 
> b/arch/x86/platform/pvh/enlighten.c
> index 
> f2053cbe9b0ce3d2178938269607c652ae8f528e..cb442cbd9d828619421babb281bfe9759edbca8a
>  100644
> --- a/arch/x86/platform/pvh/enlighten.c
> +++ b/arch/x86/platform/pvh/enlighten.c
> @@ -8,6 +8,7 @@
>  #include <asm/hypervisor.h>
>  #include <asm/e820/api.h>
>  #include <asm/x86_init.h>
> +#include <asm/string.h>
>  
>  #include <asm/xen/interface.h>
>  
> @@ -129,7 +130,7 @@ void __init xen_prepare_pvh(void)
>        * This must not compile to "call memset" because memset() may be
>        * instrumented.
>        */
> -     __builtin_memset(&pvh_bootparams, 0, sizeof(pvh_bootparams));
> +     __inline_memset(&pvh_bootparams, 0, sizeof(pvh_bootparams));
>  
>       hypervisor_specific_init(xen_guest);
>  
> 
> -- 

Why is this a separate patch from 4/5 if it is fixing the same thing?

-- 
Regards/Gruss,
    Boris.

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