Re: [Qemu-devel] [PATCH v3 1/5] hw/i386: allow SHPC for Q35 machine

[Michael S. Tsirkin]

On Sat, Jul 29, 2017 at 02:37:49AM +0300, Aleksandr Bezzubikov wrote:
> Unmask previously masked SHPC feature in _OSC method.
> 
> Signed-off-by: Aleksandr Bezzubikov <address@hidden>

This does not do what the subject says - it enables
SHPC unconditionally. And I think it will actually break
ACPI hotplug for the PC unless we add an interface to
disable ACPI hotplug and enable SHPC.

Pls limit to Q35 only.

> ---
>  hw/i386/acpi-build.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 6b7bade..2ab32f9 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -1848,9 +1848,9 @@ static Aml *build_q35_osc_method(void)
>  
>      /*
>       * Always allow native PME, AER (no dependencies)
> -     * Never allow SHPC (no SHPC controller in this system)
> +     * Allow SHPC (PCI bridges can have SHPC controller)
>       */
> -    aml_append(if_ctx, aml_and(a_ctrl, aml_int(0x1D), a_ctrl));
> +    aml_append(if_ctx, aml_and(a_ctrl, aml_int(0x1F), a_ctrl));
>  
>      if_ctx2 = aml_if(aml_lnot(aml_equal(aml_arg(1), aml_int(1))));
>      /* Unknown revision */
> -- 
> 2.7.4