Previously KVM ignored the mod field of MOVBE instruction, so MOVBE from
register to register succeeds, although it should fail (cause a #UD exception).
This test check that a #UD is indeed delivered upon such MOVBE.
The test would not work if MOVBE is unsupported.
Signed-off-by: Nadav Amit <namit@xxxxxxxxxxxxxxxxx>
---
x86/emulator.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/x86/emulator.c b/x86/emulator.c
index 5aa4dbf..709978b 100644
--- a/x86/emulator.c
+++ b/x86/emulator.c
@@ -1051,6 +1051,27 @@ static void test_simplealu(u32 *mem)
report("test", *mem == 0x8400);
}
+static void illegal_movbe_handler(struct ex_regs *regs)
+{
+ extern char bad_movbe_cont;
+
+ ++exceptions;
+ regs->rip = (ulong)&bad_movbe_cont;
+}
+
+static void test_illegal_movbe(void)
+{
+ if (!(cpuid(1).c & (1 << 22)))
+ printf("SKIP: illegal movbe\n");
+
+ exceptions = 0;
+ handle_exception(UD_VECTOR, illegal_movbe_handler);
+ asm volatile(".byte 0x0f; .byte 0x38; .byte 0xf0; .byte 0xc0;\n\t"
+ " bad_movbe_cont:" : : : "rax");
+ report("illegal movbe", exceptions == 1);
+ handle_exception(UD_VECTOR, 0);
+}
+
int main()
{
void *mem;
@@ -1119,6 +1140,7 @@ int main()
test_string_io_mmio(mem);
test_jmp_noncanonical(mem);
+ test_illegal_movbe();
return report_summary();
}
--
1.9.1
--
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