Hi Philippe,
---- On Mon, 26 May 2025 18:07:16 +0800 Philippe Mathieu-Daudé
<phi...@linaro.org> wrote ---
> Hi Li,
>
> On 15/5/25 14:41, Li Chen wrote:
> > From: Li Chen <chenl...@chinatelecom.cn>
> >
> > The ACPI SPCR (Serial Port Console Redirection) table allows firmware
> > to specify a preferred serial console device to the operating system.
> > On ARM64 systems, Linux by default respects this table: even if the
> > kernel command line does not include a hardware serial console (e.g.,
> > "console=ttyAMA0"), the kernel still register the serial device
> > referenced by SPCR as a printk console.
> >
> > While this behavior is standard-compliant, it can lead to situations
> > where guest console behavior is influenced by platform firmware rather
> > than user-specified configuration. To make guest console behavior more
> > predictable and under user control, this patch introduces a machine
> > option to explicitly disable SPCR table exposure:
> >
> > -machine spcr=off
> >
> > By default, the option is enabled (spcr=on), preserving existing
> > behavior. When disabled, QEMU will omit the SPCR table from the guest's
> > ACPI namespace, ensuring that only consoles explicitly declared in the
> > kernel command line are registered.
> >
> > Signed-off-by: Li Chen <chenl...@chinatelecom.cn>
> > Reviewed-by: Bibo Mao <maob...@loongson.cn>
> > Acked-by: Michael S. Tsirkin <m...@redhat.com>
> > Reviewed-by: Gavin Shan <gs...@redhat.com>
> > ---
>
>
> > diff --git a/include/hw/boards.h b/include/hw/boards.h
> > index 765dc8dd35..089104d54b 100644
> > --- a/include/hw/boards.h
> > +++ b/include/hw/boards.h
> > @@ -444,6 +444,7 @@ struct MachineState {
> > SmpCache smp_cache;
> > struct NVDIMMState *nvdimms_state;
> > struct NumaState *numa_state;
> > + bool enable_spcr;
>
> This structure is used by all machines. Can we be more
> descriptive, maybe naming as "acpi_spcr_enabled"?
Make sense to me, updated in v4, thanks!
(But I'm not sure why v4 failed to send to qemu-devel/qemu-arm/qemu-riscv and
report
"Message headers fail syntax check" error).
Regards,
Li
