Advertise the location of bootable RAM to kexec-tools. kexec needs to
know where it can place the kernel in RAM, and so be executable when
the system needs to jump into it.
Advertise these areas in /proc/iomem with a "System RAM (boot alias)"
tag.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
arch/arm/kernel/setup.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 19b25ad61385..7cf1c0d4f773 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -847,10 +847,29 @@ static void __init request_standard_resources(const struct machine_desc *mdesc)
kernel_data.end = virt_to_phys(_end - 1);
for_each_memblock(memory, region) {
+ phys_addr_t start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
+ phys_addr_t end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
+ unsigned long boot_alias_start;
+
+ /*
+ * Some systems have a special memory alias which is only
+ * used for booting. We need to advertise this region to
+ * kexec-tools so they know where bootable RAM is located.
+ */
+ boot_alias_start = phys_to_idmap(start);
+ if (arm_has_idmap_alias() && boot_alias_start != INVALID_IDMAP_ADDR) {
+ res = memblock_virt_alloc(sizeof(*res), 0);
+ res->name = "System RAM (boot alias)";
+ res->start = boot_alias_start;
+ res->end = phys_to_idmap(end);
+ res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ request_resource(&iomem_resource, res);
+ }
+
res = memblock_virt_alloc(sizeof(*res), 0);
res->name = "System RAM";
- res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
- res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
+ res->start = start;
+ res->end = end;
res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
request_resource(&iomem_resource, res);
--
2.1.0
