[PATCH v7 043/102] KVM: x86/mmu: Focibly use TDP MMU for TDX

isaku.yamahata
2022-06-27T21:56:32Z

From: Isaku Yamahata <isaku.yamahata@intel.com>

In this patch series, TDX supports only TDP MMU and doesn't support legacy
MMU. Forcibly use TDP MMU for TDX irrelevant of kernel parameter to
disable TDP MMU.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
arch/x86/kvm/mmu/tdp_mmu.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 82f1bfac7ee6..7eb41b176d1e 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -18,8 +18,13 @@ int kvm_mmu_init_tdp_mmu(struct kvm *kvm)
{
struct workqueue_struct *wq;

- if (!tdp_enabled || !READ_ONCE(tdp_mmu_enabled))
- return 0;
+ /*
+ * Because TDX supports only TDP MMU, forcibly use TDP MMU in the case
+ * of TDX.
+ */
+ if (kvm->arch.vm_type != KVM_X86_TDX_VM &&
+ (!tdp_enabled || !READ_ONCE(tdp_mmu_enabled)))
+ return false;

wq = alloc_workqueue("kvm", WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 0);
if (!wq)
--
2.25.1