KVM: x86: manually unroll bad_mt_xwr loop
The loop is computing one of two constants, it can be simpler to write
everything inline.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index c3f39aa..b8482c0 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3706,7 +3706,7 @@
__reset_rsvds_bits_mask_ept(struct rsvd_bits_validate *rsvd_check,
int maxphyaddr, bool execonly)
{
- int pte;
+ u64 bad_mt_xwr;
rsvd_check->rsvd_bits_mask[0][3] =
rsvd_bits(maxphyaddr, 51) | rsvd_bits(3, 7);
@@ -3724,14 +3724,16 @@
rsvd_bits(maxphyaddr, 51) | rsvd_bits(12, 20);
rsvd_check->rsvd_bits_mask[1][0] = rsvd_check->rsvd_bits_mask[0][0];
- for (pte = 0; pte < 64; pte++) {
- int rwx_bits = pte & 7;
- int mt = pte >> 3;
- if (mt == 0x2 || mt == 0x3 || mt == 0x7 ||
- rwx_bits == 0x2 || rwx_bits == 0x6 ||
- (rwx_bits == 0x4 && !execonly))
- rsvd_check->bad_mt_xwr |= (1ull << pte);
+ bad_mt_xwr = 0xFFull << (2 * 8); /* bits 3..5 must not be 2 */
+ bad_mt_xwr |= 0xFFull << (3 * 8); /* bits 3..5 must not be 3 */
+ bad_mt_xwr |= 0xFFull << (7 * 8); /* bits 3..5 must not be 7 */
+ bad_mt_xwr |= REPEAT_BYTE(1ull << 2); /* bits 0..2 must not be 010 */
+ bad_mt_xwr |= REPEAT_BYTE(1ull << 6); /* bits 0..2 must not be 110 */
+ if (!execonly) {
+ /* bits 0..2 must not be 100 unless VMX capabilities allow it */
+ bad_mt_xwr |= REPEAT_BYTE(1ull << 4);
}
+ rsvd_check->bad_mt_xwr = bad_mt_xwr;
}
static void reset_rsvds_bits_mask_ept(struct kvm_vcpu *vcpu,