The current emulation of bit operations ignores the offset from the destination
on 64-bit target memory operands. This patch fixes this behavior.

Signed-off-by: Nadav Amit <na...@cs.technion.ac.il>
---
 arch/x86/kvm/emulate.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index e4e833d..f0b0a10 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1220,12 +1220,14 @@ static void fetch_bit_operand(struct x86_emulate_ctxt 
*ctxt)
        long sv = 0, mask;
 
        if (ctxt->dst.type == OP_MEM && ctxt->src.type == OP_REG) {
-               mask = ~(ctxt->dst.bytes * 8 - 1);
+               mask = ~((long)ctxt->dst.bytes * 8 - 1);
 
                if (ctxt->src.bytes == 2)
                        sv = (s16)ctxt->src.val & (s16)mask;
                else if (ctxt->src.bytes == 4)
                        sv = (s32)ctxt->src.val & (s32)mask;
+               else
+                       sv = (s64)ctxt->src.val & (s64)mask;
 
                ctxt->dst.addr.mem.ea += (sv >> 3);
        }
-- 
1.9.1

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