Re: [kvm-unit-tests PATCH] x86: realmode: Test interrupt delivery after STI

[Roman Bolshakov <r.bolshakov@yadro.com>]

n Sun, Mar 29, 2020 at 10:11:25AM +0300, Roman Bolshakov wrote:
> If interrupts are disabled, STI is inhibiting interrupts for the
> instruction following it. If STI is followed by HLT, the CPU is going to
> handle all pending or new interrupts as soon as HLT is executed.
> 
> Test if emulator properly clears inhibition state and allows the
> scenario outlined above.
> 
> Cc: Cameron Esfahani <dirty@apple.com>
> Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
> ---
>  x86/realmode.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/x86/realmode.c b/x86/realmode.c
> index 31f84d0..3518224 100644
> --- a/x86/realmode.c
> +++ b/x86/realmode.c
> @@ -814,6 +814,26 @@ static void test_int(void)
>  	report("int 1", 0, 1);
>  }
>  
> +static void test_sti_inhibit(void)
> +{
> +	init_inregs(NULL);
> +
> +	*(u32 *)(0x73 * 4) = 0x1000; /* Store IRQ 11 handler in the IDT */
> +	*(u8 *)(0x1000) = 0xcf; /* 0x1000 contains an IRET instruction */
> +
> +	MK_INSN(sti_inhibit, "cli\n\t"
> +			     "movw $0x200b, %dx\n\t"
> +			     "movl $1, %eax\n\t"
> +			     "outl %eax, %dx\n\t" /* Set IRQ11 */
> +			     "movl $0, %eax\n\t"
> +			     "outl %eax, %dx\n\t" /* Clear IRQ11 */
> +			     "sti\n\t"
> +			     "hlt\n\t");
> +	exec_in_big_real_mode(&insn_sti_inhibit);
> +
> +	report("sti inhibit", ~0, 1);
> +}
> +
>  static void test_imul(void)
>  {
>  	MK_INSN(imul8_1, "mov $2, %al\n\t"
> @@ -1739,6 +1759,7 @@ void realmode_start(void)
>  	test_xchg();
>  	test_iret();
>  	test_int();
> +	test_sti_inhibit();
>  	test_imul();
>  	test_mul();
>  	test_div();
> -- 
> 2.24.1
> 

Hi,

Should I resend the patch?
And this one: https://patchwork.kernel.org/cover/11449525/ ?

Thanks,
Roman