> On Jun 26, 2020, at 12:05 AM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 25/06/20 21:18, Paolo Bonzini wrote:
>> On 25/06/20 20:59, Nadav Amit wrote:
>>> I think that there is a hidden assumption about the IDT location in
>>> realmode’s test_int(), which this would break:
>>>
>>> static void test_int(void)
>>> {
>>> init_inregs(NULL);
>>>
>>> boot_idt[11] = 0x1000; /* Store a pointer to address 0x1000 in IDT entry 0x11 */
>>> *(u8 *)(0x1000) = 0xcf; /* 0x1000 contains an IRET instruction */
>>>
>>> MK_INSN(int11, "int $0x11\n\t");
>>>
>>> exec_in_big_real_mode(&insn_int11);
>>> report("int 1", 0, 1);
>>> }
>>
>> Uuuuuuuuuuuuuuuumph... you're right. :( Will send a patch tomorrow.
>
> Actually the IDTR is not reloaded by exec_in_big_real_mode, so this
> (while a bit weird) works fine.
Err… So it means I need to debug why it does not work for *me*…
