Use the new flag X86EMUL_F_BRANCH instead of X86EMUL_F_FETCH in assign_eip()
to distinguish instruction fetch and branch target computation for features
that handle differently on them, e.g. Linear Address Space Separation (LASS).
As of this patch, X86EMUL_F_BRANCH and X86EMUL_F_FETCH are identical as far
as KVM is concerned.
No functional change intended.
Signed-off-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
Tested-by: Xuelian Guo <xuelian.guo@xxxxxxxxx>
---
arch/x86/kvm/emulate.c | 5 +++--
arch/x86/kvm/kvm_emulate.h | 1 +
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 87ee1802166a..274d6e7aa0c1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -721,7 +721,8 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
(flags & X86EMUL_F_WRITE))
goto bad;
/* unreadable code segment */
- if (!(flags & X86EMUL_F_FETCH) && (desc.type & 8) && !(desc.type & 2))
+ if (!(flags & (X86EMUL_F_FETCH | X86EMUL_F_BRANCH)) &&
+ (desc.type & 8) && !(desc.type & 2))
goto bad;
lim = desc_limit_scaled(&desc);
if (!(desc.type & 8) && (desc.type & 4)) {
@@ -772,7 +773,7 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
if (ctxt->op_bytes != sizeof(unsigned long))
addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
rc = __linearize(ctxt, addr, &max_size, 1, ctxt->mode, &linear,
- X86EMUL_F_FETCH);
+ X86EMUL_F_BRANCH);
if (rc == X86EMUL_CONTINUE)
ctxt->_eip = addr.ea;
return rc;
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index e24c8ac7b930..e1fd83908334 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -91,6 +91,7 @@ struct x86_instruction_info {
/* x86-specific emulation flags */
#define X86EMUL_F_WRITE BIT(0)
#define X86EMUL_F_FETCH BIT(1)
+#define X86EMUL_F_BRANCH BIT(2)
struct x86_emulate_ops {
void (*vm_bugged)(struct x86_emulate_ctxt *ctxt);
--
2.25.1
