From: Nadav Amit <namit@cs.technion.ac.il>
Date: Wed, 19 Nov 2014 15:43:12 +0000 (+0200)
Subject: KVM: x86: Non-canonical access using SS should cause #SS
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=abc7d8a4c935dbe0be5db2eb338b2ec9b27ae157;p=linux-beck.git

KVM: x86: Non-canonical access using SS should cause #SS

When SS is used using a non-canonical address, an #SS exception is generated on
real hardware.  KVM emulator causes a #GP instead. Fix it to behave as real x86
CPU.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 4d083fb9dd8e..57dc0d79c10e 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -635,7 +635,7 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
 	switch (mode) {
 	case X86EMUL_MODE_PROT64:
 		if (is_noncanonical_address(la))
-			return emulate_gp(ctxt, 0);
+			goto bad;
 
 		*max_size = min_t(u64, ~0u, (1ull << 48) - la);
 		if (size > *max_size)