From: Ard Biesheuvel ard.biesheuvel@linaro.org
[ Upstream commit 3ea86495aef2f6de26b7cb1599ba350dd6a0c521 ]
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 ard.biesheuvel@linaro.org [will: fold in EFI_MEMMAP attribute check from Ard] Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- 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 80d1a885def5..a7c522eac640 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 86a1ad17a32e..8995a48bd067 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -122,11 +122,13 @@ 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;