From 3ea86495aef2f6de26b7cb1599ba350dd6a0c521 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 23 Jul 2018 10:57:30 +0900 Subject: [PATCH] efi/arm: preserve early mapping of UEFI memory map longer for BGRT The BGRT code validates the contents of the table against the UEFI memory map, and so it expects it to be mapped when the code runs. On ARM, this is currently not the case, since we tear down the early mapping after efi_init() completes, and only create the permanent mapping in arm_enable_runtime_services(), which executes as an early initcall, but still leaves a window where the UEFI memory map is not mapped. So move the call to efi_memmap_unmap() from efi_init() to arm_enable_runtime_services(). Signed-off-by: Ard Biesheuvel [will: fold in EFI_MEMMAP attribute check from Ard] Signed-off-by: Will Deacon --- drivers/firmware/efi/arm-init.c | 1 - drivers/firmware/efi/arm-runtime.c | 4 +++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c index b5214c1..388a929 100644 --- a/drivers/firmware/efi/arm-init.c +++ b/drivers/firmware/efi/arm-init.c @@ -259,7 +259,6 @@ void __init efi_init(void) reserve_regions(); efi_esrt_init(); - efi_memmap_unmap(); memblock_reserve(params.mmap & PAGE_MASK, PAGE_ALIGN(params.mmap_size + diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c index 5889cbe..4712445 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -110,11 +110,13 @@ static int __init arm_enable_runtime_services(void) { u64 mapsize; - if (!efi_enabled(EFI_BOOT)) { + if (!efi_enabled(EFI_BOOT) || !efi_enabled(EFI_MEMMAP)) { pr_info("EFI services will not be available.\n"); return 0; } + efi_memmap_unmap(); + if (efi_runtime_disabled()) { pr_info("EFI runtime services will be disabled.\n"); return 0; -- 2.7.4