[PATCH 2/5] kvm: x86: mmu: Set SPTE_SPECIAL_MASK within mmu.c

Junaid Shahid
2016-12-22T04:29:36Z

Instead of the caller including the SPTE_SPECIAL_MASK in the masks being
supplied to kvm_mmu_set_mmio_spte_mask() and kvm_mmu_set_mask_ptes(),
those functions now themselves include the SPTE_SPECIAL_MASK.

Signed-off-by: Junaid Shahid <junaids@google.com>
---
arch/x86/kvm/mmu.c | 5 ++++-
arch/x86/kvm/vmx.c | 6 ++----
arch/x86/kvm/x86.c | 3 ---
3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 3e42fcd..8707084 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -207,7 +207,7 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu);

void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask)
{
- shadow_mmio_mask = mmio_mask;
+ shadow_mmio_mask = mmio_mask | SPTE_SPECIAL_MASK;
}
EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask);

@@ -317,6 +317,9 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
u64 dirty_mask, u64 nx_mask, u64 x_mask, u64 p_mask,
u64 acc_track_mask)
{
+ if (acc_track_mask != 0)
+ acc_track_mask |= SPTE_SPECIAL_MASK;
+
shadow_user_mask = user_mask;
shadow_accessed_mask = accessed_mask;
shadow_dirty_mask = dirty_mask;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3f83856..3744dbb 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5228,10 +5228,8 @@ static void ept_set_mmio_spte_mask(void)
/*
* EPT Misconfigurations can be generated if the value of bits 2:0
* of an EPT paging-structure entry is 110b (write/execute).
- * Also, special bit (62) is set to quickly identify mmio spte.
*/
- kvm_mmu_set_mmio_spte_mask(SPTE_SPECIAL_MASK |
- VMX_EPT_MISCONFIG_WX_VALUE);
+ kvm_mmu_set_mmio_spte_mask(VMX_EPT_MISCONFIG_WX_VALUE);
}

#define VMX_XSS_EXIT_BITMAP 0
@@ -6577,7 +6575,7 @@ void vmx_enable_tdp(void)
enable_ept_ad_bits ? VMX_EPT_DIRTY_BIT : 0ull,
0ull, VMX_EPT_EXECUTABLE_MASK,
cpu_has_vmx_ept_execute_only() ? 0ull : VMX_EPT_READABLE_MASK,
- enable_ept_ad_bits ? 0ull : SPTE_SPECIAL_MASK | VMX_EPT_RWX_MASK);
+ enable_ept_ad_bits ? 0ull : VMX_EPT_RWX_MASK);

ept_set_mmio_spte_mask();
kvm_enable_tdp();
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fb52d66..51c3a4d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5944,9 +5944,6 @@ static void kvm_set_mmio_spte_mask(void)
/* Mask the reserved physical address bits. */
mask = rsvd_bits(maxphyaddr, 51);

- /* Bit 62 is always reserved for 32bit host. */
- mask |= 0x3ull << 62;
-
/* Set the present bit. */
mask |= 1ull;

--
2.8.0.rc3.226.g39d4020