[PATCH 06/28] KVM: x86/mmu: merge make_spte_{non,}executable

Paolo Bonzini
2026-04-28T11:09:56Z

As the logic will become more complicated with the introduction
of MBEC, at least write it only once.

Tested-by: David Riley <d.riley@proxmox.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/mmu/spte.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index 85a0473809b0..e9dc0ae44274 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -317,14 +317,16 @@ static u64 modify_spte_protections(u64 spte, u64 set, u64 clear)
return spte;
}

-static u64 make_spte_executable(u64 spte)
+static u64 make_spte_executable(u64 spte, u8 access)
{
- return modify_spte_protections(spte, shadow_x_mask, shadow_nx_mask);
-}
+ u64 set, clear;

-static u64 make_spte_nonexecutable(u64 spte)
-{
- return modify_spte_protections(spte, shadow_nx_mask, shadow_x_mask);
+ if (access & ACC_EXEC_MASK)
+ set = shadow_x_mask;
+ else
+ set = shadow_nx_mask;
+ clear = set ^ (shadow_nx_mask | shadow_x_mask);
+ return modify_spte_protections(spte, set, clear);
}

/*
@@ -356,8 +358,8 @@ u64 make_small_spte(struct kvm *kvm, u64 huge_spte,
* the page executable as the NX hugepage mitigation no longer
* applies.
*/
- if ((role.access & ACC_EXEC_MASK) && is_nx_huge_page_enabled(kvm))
- child_spte = make_spte_executable(child_spte);
+ if (is_nx_huge_page_enabled(kvm))
+ child_spte = make_spte_executable(child_spte, role.access);
}

return child_spte;
@@ -379,7 +381,7 @@ u64 make_huge_spte(struct kvm *kvm, u64 small_spte, int level)
huge_spte &= KVM_HPAGE_MASK(level) | ~PAGE_MASK;

if (is_nx_huge_page_enabled(kvm))
- huge_spte = make_spte_nonexecutable(huge_spte);
+ huge_spte = make_spte_executable(huge_spte, 0);

return huge_spte;
}
--
2.52.0