From dca0f971ea6fcf2f1bb78f7995adf80da9f4767f Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Sat, 27 Feb 2016 15:52:50 +0000 Subject: efi: Add efi_memmap_init_late() for permanent EFI memmap Drivers need a way to access the EFI memory map at runtime. ARM and arm64 currently provide this by remapping the EFI memory map into the vmalloc space before setting up the EFI virtual mappings. x86 does not provide this functionality which has resulted in the code in efi_mem_desc_lookup() where it will manually map individual EFI memmap entries if the memmap has already been torn down on x86, /* * If a driver calls this after efi_free_boot_services, * ->map will be NULL, and the target may also not be mapped. * So just always get our own virtual map on the CPU. * */ md = early_memremap(p, sizeof (*md)); There isn't a good reason for not providing a permanent EFI memory map for runtime queries, especially since the EFI regions are not mapped into the standard kernel page tables. Tested-by: Dave Young [kexec/kdump] Tested-by: Ard Biesheuvel [arm] Acked-by: Ard Biesheuvel Cc: Leif Lindholm Cc: Peter Jones Cc: Borislav Petkov Cc: Mark Rutland Signed-off-by: Matt Fleming --- drivers/firmware/efi/arm-runtime.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/firmware/efi/arm-runtime.c') diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c index eedb30351a68..ae001450545f 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -116,12 +116,10 @@ static int __init arm_enable_runtime_services(void) mapsize = efi.memmap.desc_size * efi.memmap.nr_map; - efi.memmap.map = memremap(efi.memmap.phys_map, mapsize, MEMREMAP_WB); - if (!efi.memmap.map) { + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { pr_err("Failed to remap EFI memory map\n"); return -ENOMEM; } - efi.memmap.map_end = efi.memmap.map + mapsize; if (!efi_virtmap_init()) { pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); -- cgit v1.2.3