linux-kernel - [PATCH v2 61/66] KVM: x86: Don't propagate MMU lpage support to memslot.disallow

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Date:   Mon,  2 Mar 2020 15:57:04 -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, Xiaoyao Li <xiaoyao.li@...el.com>
Subject: [PATCH v2 61/66] 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.

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>
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 f8eb081b63fe..1fbe54dc3263 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7698,9 +7698,6 @@ 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 4fdf5b04f148..cc9b543d210b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9863,11 +9863,9 @@ static int kvm_alloc_memslot_metadata(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