Re: [PATCH v7 10/21] KVM: s390: vsie: Refactor kvm_s390_vsie_destroy and extract reusable methods

[Janosch Frank <frankja@linux.ibm.com>]

On 9/18/26 5:09 PM, Christoph Schlameuss wrote:
> Create a helper method release_gmap_shadow_safe() to simplify releasing
> the gmap shadow of a vsie_page and a method kvm_s390_vsie_destroy_page()
> reduce nesting.
> Both methods will be called from multiple places in upcoming patches.
> 
> Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
> ---
>   arch/s390/kvm/s390/vsie.c | 42 +++++++++++++++++++++++++++---------------
>   1 file changed, 27 insertions(+), 15 deletions(-)
> 
> diff --git a/arch/s390/kvm/s390/vsie.c b/arch/s390/kvm/s390/vsie.c
> index 75676f493ab2..78d59fc535f7 100644
> --- a/arch/s390/kvm/s390/vsie.c
> +++ b/arch/s390/kvm/s390/vsie.c
> @@ -164,6 +164,17 @@ static void release_gmap_shadow(struct vsie_page *vsie_page)
>   	}
>   }
>   
> +static void release_gmap_shadow_safe(struct kvm *kvm, struct vsie_page *vsie_page)

I'd prefer a "locking" suffix or something similar.
If people have the bright idea to use this instead of the normal 
function and grab the lock outside of this function then we're in a pickle.

The rest is fine.

> +{
> +	if (!vsie_page->gmap_cache.gmap)
> +		return;
> +
> +	guard(spinlock)(&kvm->arch.gmap->children_lock);
> +
> +	if (vsie_page->gmap_cache.gmap)
> +		release_gmap_shadow(vsie_page);
> +}
> +