linux-kernel - [PATCH 59/61] KVM: x86: Don't propagate MMU lpage support to memslot.disallow

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Message-Id: <20200201185218.24473-60-sean.j.christopherson@intel.com>
Date:   Sat,  1 Feb 2020 10:52:16 -0800
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 59/61] KVM: x86: Don't propagate MMU lpage support to memslot.disallow_lpage

Stop propagating MMU large page support into a memslot's disallow_lpage
now that the MMU's max_page_level handles the scenario where VMX's EPT is
enabled and EPT doesn't support 2M pages.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/vmx/vmx.c | 3 ---
 arch/x86/kvm/x86.c     | 6 ++----
 2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 3ad24ca692a6..e349689ac0cf 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7633,9 +7633,6 @@ static __init int hardware_setup(void)
 	if (!cpu_has_vmx_tpr_shadow())
 		kvm_x86_ops->update_cr8_intercept = NULL;
 
-	if (enable_ept && !cpu_has_vmx_ept_2m_page())
-		kvm_disable_largepages();
-
 #if IS_ENABLED(CONFIG_HYPERV)
 	if (ms_hyperv.nested_features & HV_X64_NESTED_GUEST_MAPPING_FLUSH
 	    && enable_ept) {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 144143a57d0b..b40488fd2969 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9884,11 +9884,9 @@ int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
 		ugfn = slot->userspace_addr >> PAGE_SHIFT;
 		/*
 		 * If the gfn and userspace address are not aligned wrt each
-		 * other, or if explicitly asked to, disable large page
-		 * support for this slot
+		 * other, disable large page support for this slot.
 		 */
-		if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
-		    !kvm_largepages_enabled()) {
+		if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1)) {
 			unsigned long j;
 
 			for (j = 0; j < lpages; ++j)
-- 
2.24.1