diff options
| author | Xiao Guangrong <[email protected]> | 2013-06-07 16:51:23 +0800 |
|---|---|---|
| committer | Paolo Bonzini <[email protected]> | 2013-06-20 23:33:20 +0200 |
| commit | 885032b91042288f98d3888c2aaf3a108d348d5c (patch) | |
| tree | 3f51f6eca75275a2be2a2cf19be546bc6ec27855 | |
| parent | 87d41fb4da6467622b7a87fd6afe8071abab6dae (diff) | |
KVM: MMU: retain more available bits on mmio spte
Let mmio spte only use bit62 and bit63 on upper 32 bits, then bit 52 ~ bit 61
can be used for other purposes
Signed-off-by: Xiao Guangrong <[email protected]>
Reviewed-by: Gleb Natapov <[email protected]>
Reviewed-by: Marcelo Tosatti <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
| -rw-r--r-- | arch/x86/kvm/vmx.c | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 8 |
2 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 260a91939555..78ee123de7a3 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4176,10 +4176,10 @@ 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, magic bits (0xffull << 49) is set to quickly identify mmio + * Also, magic bits (0x3ull << 62) is set to quickly identify mmio * spte. */ - kvm_mmu_set_mmio_spte_mask(0xffull << 49 | 0x6ull); + kvm_mmu_set_mmio_spte_mask((0x3ull << 62) | 0x6ull); } /* diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 737c804b310c..15cf34d4ae95 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5280,7 +5280,13 @@ static void kvm_set_mmio_spte_mask(void) * Set the reserved bits and the present bit of an paging-structure * entry to generate page fault with PFER.RSV = 1. */ - mask = ((1ull << (62 - maxphyaddr + 1)) - 1) << maxphyaddr; + /* Mask the reserved physical address bits. */ + mask = ((1ull << (51 - maxphyaddr + 1)) - 1) << maxphyaddr; + + /* Bit 62 is always reserved for 32bit host. */ + mask |= 0x3ull << 62; + + /* Set the present bit. */ mask |= 1ull; #ifdef CONFIG_X86_64 |