Commit 059717c2 authored May 23, 2025 by Anil S Keshavamurthy Committed by Rafael J. Wysocki May 23, 2025

ACPI: MRRM: Fix default max memory region



Per the spec, the default max memory region must be 1 covering
all system memory.

When platform does not provide ACPI MRRM table or
when CONFIG_ACPI is opted out, the acpi_mrrm_max_mem_region() function
defaults to  returning 1 region complying to RDT spec.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://patch.msgid.link/20250523172001.1761634-1-anil.s.keshavamurthy@intel.com


Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 8e66be07

drivers/acpi/acpi_mrrm.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -14,7 +14,8 @@
		#include <linux/string.h>
		#include <linux/sysfs.h>

		static int max_mem_region = -ENOENT;
		/* Default assume one memory region covering all system memory, per the spec */
		static int max_mem_region = 1;

		/* Access for use by resctrl file system */
		int acpi_mrrm_max_mem_region(void)

include/linux/acpi.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -1098,7 +1098,7 @@ static inline acpi_handle acpi_get_processor_handle(int cpu)

		static inline int acpi_mrrm_max_mem_region(void)
		{
		return -ENOENT;
		return 1;
		}

		#endif /* !CONFIG_ACPI */