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Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c35
1 files changed, 27 insertions, 8 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 9da95b9daf8d..1505587d06e9 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2272,8 +2272,8 @@ static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt)
#define GET_SMSTATE(type, smbase, offset) \
({ \
type __val; \
- int r = ctxt->ops->read_std(ctxt, smbase + offset, &__val, \
- sizeof(__val), NULL); \
+ int r = ctxt->ops->read_phys(ctxt, smbase + offset, &__val, \
+ sizeof(__val)); \
if (r != X86EMUL_CONTINUE) \
return X86EMUL_UNHANDLEABLE; \
__val; \
@@ -2484,17 +2484,36 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
/*
* Get back to real mode, to prepare a safe state in which to load
- * CR0/CR3/CR4/EFER. Also this will ensure that addresses passed
- * to read_std/write_std are not virtual.
- *
- * CR4.PCIDE must be zero, because it is a 64-bit mode only feature.
+ * CR0/CR3/CR4/EFER. It's all a bit more complicated if the vCPU
+ * supports long mode.
*/
+ cr4 = ctxt->ops->get_cr(ctxt, 4);
+ if (emulator_has_longmode(ctxt)) {
+ struct desc_struct cs_desc;
+
+ /* Zero CR4.PCIDE before CR0.PG. */
+ if (cr4 & X86_CR4_PCIDE) {
+ ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
+ cr4 &= ~X86_CR4_PCIDE;
+ }
+
+ /* A 32-bit code segment is required to clear EFER.LMA. */
+ memset(&cs_desc, 0, sizeof(cs_desc));
+ cs_desc.type = 0xb;
+ cs_desc.s = cs_desc.g = cs_desc.p = 1;
+ ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS);
+ }
+
+ /* For the 64-bit case, this will clear EFER.LMA. */
cr0 = ctxt->ops->get_cr(ctxt, 0);
if (cr0 & X86_CR0_PE)
ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
- cr4 = ctxt->ops->get_cr(ctxt, 4);
+
+ /* Now clear CR4.PAE (which must be done before clearing EFER.LME). */
if (cr4 & X86_CR4_PAE)
ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE);
+
+ /* And finally go back to 32-bit mode. */
efer = 0;
ctxt->ops->set_msr(ctxt, MSR_EFER, efer);
@@ -4455,7 +4474,7 @@ static const struct opcode twobyte_table[256] = {
F(DstMem | SrcReg | Src2CL | ModRM, em_shld), N, N,
/* 0xA8 - 0xAF */
I(Stack | Src2GS, em_push_sreg), I(Stack | Src2GS, em_pop_sreg),
- II(No64 | EmulateOnUD | ImplicitOps, em_rsm, rsm),
+ II(EmulateOnUD | ImplicitOps, em_rsm, rsm),
F(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_bts),
F(DstMem | SrcReg | Src2ImmByte | ModRM, em_shrd),
F(DstMem | SrcReg | Src2CL | ModRM, em_shrd),