Messages in this thread Patch in this message | | | From | Nadav Amit <> | Subject | [PATCH kvm-unit-tests 1/3] x86: Check rflags.rf is cleared after emulation | Date | Mon, 21 Jul 2014 14:39:52 +0300 |
| |
RFLAGS.RF should be cleared after every instruction emulation. Recently discovered bug indicated this is not the case. This patch adds a test to check this behavior. It is done by setting RF, executing IRET and checking whether the saved RF is cleared. Since the flags are saved several instructions after IRET is executed, RF should be cleared.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> --- x86/realmode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/x86/realmode.c b/x86/realmode.c index 10c3e03..09e6aa7 100644 --- a/x86/realmode.c +++ b/x86/realmode.c @@ -744,7 +744,7 @@ void test_iret() MK_INSN(iret_flags32, "pushfl\n\t" "popl %eax\n\t" "andl $~0x2, %eax\n\t" - "orl $0xffc08028, %eax\n\t" + "orl $0xffc18028, %eax\n\t" "pushl %eax\n\t" "pushl %cs\n\t" "call 1f\n\t" @@ -773,6 +773,7 @@ void test_iret() exec_in_big_real_mode(&insn_iret_flags32); report("iret 3", R_AX, 1); + report("rflags.rf", ~0, !(outregs.eflags & (1 << 16))); exec_in_big_real_mode(&insn_iret_flags16); report("iret 4", R_AX, 1); -- 1.9.1
| |