[PATCH 5.15.y v2 2/8] KVM: x86/mmu: Stop passing "direct" to mmu_alloc_root()

From: Paolo Bonzini

Date: Fri Jun 26 2026 - 13:48:36 EST


From: David Matlack <dmatlack@xxxxxxxxxx>

commit 86938ab6925b8fe174ca6abf397e6ea9d3c054a4 upstream.

The "direct" argument is vcpu->arch.mmu->root_role.direct,
because unlike non-root page tables, it's impossible to have
a direct root in an indirect MMU. So just use that.

Suggested-by: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
Message-Id: <20220516232138.1783324-4-dmatlack@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c03c4341a87f..bd7650380ad9 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3409,8 +3409,9 @@ static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn)
}

static hpa_t mmu_alloc_root(struct kvm_vcpu *vcpu, gfn_t gfn, gva_t gva,
- u8 level, bool direct)
+ u8 level)
{
+ bool direct = vcpu->arch.mmu->mmu_role.base.direct;
struct kvm_mmu_page *sp;

sp = kvm_mmu_get_page(vcpu, gfn, gva, level, direct, ACC_ALL);
@@ -3436,7 +3437,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
root = kvm_tdp_mmu_get_vcpu_root_hpa(vcpu);
mmu->root_hpa = root;
} else if (shadow_root_level >= PT64_ROOT_4LEVEL) {
- root = mmu_alloc_root(vcpu, 0, 0, shadow_root_level, true);
+ root = mmu_alloc_root(vcpu, 0, 0, shadow_root_level);
mmu->root_hpa = root;
} else if (shadow_root_level == PT32E_ROOT_LEVEL) {
if (WARN_ON_ONCE(!mmu->pae_root)) {
@@ -3448,7 +3449,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
WARN_ON_ONCE(IS_VALID_PAE_ROOT(mmu->pae_root[i]));

root = mmu_alloc_root(vcpu, i << (30 - PAGE_SHIFT),
- i << 30, PT32_ROOT_LEVEL, true);
+ i << 30, PT32_ROOT_LEVEL);
mmu->pae_root[i] = root | PT_PRESENT_MASK |
shadow_me_mask;
}
@@ -3511,7 +3512,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
*/
if (mmu->root_level >= PT64_ROOT_4LEVEL) {
root = mmu_alloc_root(vcpu, root_gfn, 0,
- mmu->shadow_root_level, false);
+ mmu->shadow_root_level);
mmu->root_hpa = root;
goto set_root_pgd;
}
@@ -3557,7 +3558,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
}

root = mmu_alloc_root(vcpu, root_gfn, i << 30,
- PT32_ROOT_LEVEL, false);
+ PT32_ROOT_LEVEL);
mmu->pae_root[i] = root | pm_mask;
}

--
2.54.0