Commit f3bf1dbe authored by Thomas Gleixner's avatar Thomas Gleixner

x86/acpi: Prevent LAPIC id 0xff from being accounted

Yinghai reported that the recent changes to make the cpuid - nodeid
relationship permanent causes a cpuid ordering regression on a system which
has 2apic enabled..

The reason is that the ACPI local APIC parser has no sanity check for
apicid 0xff, which is an invalid id. So a CPU id for this invalid local
APIC id is allocated and therefor breaks the cpuid ordering.

Add a sanity check to acpi_parse_lapic() which ignores the invalid id.

Fixes: 8f54969d ("x86/acpi: Introduce persistent storage for cpuid <-> apicid mapping")
Reported-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>,
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: douly.fnst@cn.fujitsu.com,
Cc: zhugh.fnst@cn.fujitsu.com
Cc: Tony Luck <tony.luck@intel.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Lv Zheng <lv.zheng@intel.com>,
Cc: robert.moore@intel.com
Cc: linux-acpi@vger.kernel.org
Link: https://lkml.kernel.org/r/CAE9FiQVQx6FRXT-RdR7Crz4dg5LeUWHcUSy1KacjR+JgU_vGJg@mail.gmail.com
parent 2a51fe08
...@@ -233,6 +233,10 @@ acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end) ...@@ -233,6 +233,10 @@ acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end)
acpi_table_print_madt_entry(header); acpi_table_print_madt_entry(header);
/* Ignore invalid ID */
if (processor->id == 0xff)
return 0;
/* /*
* We need to register disabled CPU as well to permit * We need to register disabled CPU as well to permit
* counting disabled CPUs. This allows us to size * counting disabled CPUs. This allows us to size
......
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