case EFI_BOOT_SERVICES_DATA:
case EFI_CONVENTIONAL_MEMORY:
case EFI_PERSISTENT_MEMORY:
- pr_warn(FW_BUG "requested region covers kernel memory @ %pa\n", &phys);
- return NULL;
+ if (memblock_is_map_memory(phys) ||
+ !memblock_is_region_memory(phys, size)) {
+ pr_warn(FW_BUG "requested region covers kernel memory @ %pa\n", &phys);
+ return NULL;
+ }
+ /*
+ * Mapping kernel memory is permitted if the region in
+ * question is covered by a single memblock with the
+ * NOMAP attribute set: this enables the use of ACPI
+ * table overrides passed via initramfs, which are
+ * reserved in memory using arch_reserve_mem_area()
+ * below. As this particular use case only requires
+ * read access, fall through to the R/O mapping case.
+ */
+ fallthrough;
case EFI_RUNTIME_SERVICES_CODE:
/*
*/
if (memblock_is_map_memory(phys))
return (void __iomem *)__phys_to_virt(phys);
- /* fall through */
+ fallthrough;
default:
if (region->attribute & EFI_MEMORY_WB)
return err;
}
+
+void arch_reserve_mem_area(acpi_physical_address addr, size_t size)
+{
+ memblock_mark_nomap(addr, size);
+}