Currently a memory segment in memory map with attribute of EFI_MEMORY_UC is denoted as "System RAM" in /proc/iomem, while memory of attribute (EFI_MEMORY_WB|EFI_MEMORY_UC) is also labeled the same. The kexec utility then includes uncached memory as part of vmcore. The kdump kernel MCA'ed when it tries to save the vmcore to a disk. A normal "cached" access may cause MCAs. This patch would label memory with attribute of EFI_MEMORY_UC only as "Uncached RAM" so that kexec would know not to include it in the vmcore. I will submit a separate kexec-tools patch to the kexec list. Signed-off-by: Jay Lan <jlan@xxxxxxx>
---
arch/ia64/kernel/efi.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Index: linux/arch/ia64/kernel/efi.c
===================================================================
--- linux.orig/arch/ia64/kernel/efi.c
+++ linux/arch/ia64/kernel/efi.c
@@ -1232,9 +1232,10 @@ efi_initialize_iomem_resources(struct re
if (md->attribute & EFI_MEMORY_WP) {
name = "System ROM";
flags |= IORESOURCE_READONLY;
- } else {
- name = "System RAM";
- }
+ } else if (md->attribute == EFI_MEMORY_UC)
+ name = "Uncached RAM";
+ else
+ name = "System RAM";
break;
case EFI_ACPI_MEMORY_NVS:
|