Re: [PATCH v1 1/1] KVM: s390: Increase permitted SE header size to 1 MiB
From: Claudio Imbrenda
Date: Mon Feb 09 2026 - 12:16:34 EST
On Mon, 9 Feb 2026 16:29:25 +0100
Steffen Eiden <seiden@xxxxxxxxxxxxx> wrote:
> Relax the maximum allowed Secure Execution (SE) header size from
> 8 KiB to 1 MiB. This allows individual secure guest images to run on a
> wider range of physical machines.
>
> Signed-off-by: Steffen Eiden <seiden@xxxxxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
> ---
> arch/s390/kvm/kvm-s390.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 56a50524b3ee..3428a8d427b2 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -2744,9 +2744,9 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd)
> if (copy_from_user(&parms, argp, sizeof(parms)))
> break;
>
> - /* Currently restricted to 8KB */
> + /* Currently restricted to 1MiB */
> r = -EINVAL;
> - if (parms.length > PAGE_SIZE * 2)
> + if (parms.length > SZ_1M)
> break;
>
> r = -ENOMEM;