[Qemu-devel] [PATCH v2] i386/acpi: add _HID to processor objects

[Matthias Lange]

This patch appends "ACPI0007" as the HID to each processor object.

Until commit 20843d processor objects used to have a _HID. According
to the ACPI spec this is not required but removing it breaks systems
which relied on the HID. As it does no harm it is safe to add _HID
to processor objects and restore the old behaviour.

Signed-off-by: Matthias Lange <address@hidden>
---
 hw/i386/acpi-build.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 95e0c65..314cd0b 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -1153,6 +1153,9 @@ build_ssdt(GArray *table_data, GArray *linker,
         for (i = 0; i < acpi_cpus; i++) {
             dev = aml_processor(i, 0, 0, "CP%.02X", i);
 
+            /* for processor objects a _HID is not strictly required, however 
it
+             * does no harm and preserves compatibility with other BIOSes */
+            aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0007")));
             method = aml_method("_MAT", 0);
             aml_append(method, aml_return(aml_call1("CPMA", aml_int(i))));
             aml_append(dev, method);
-- 
1.9.1