From 33412b8673135b18ea42beb7f5117ed0091798b6 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 14 Nov 2018 09:55:41 -0800 Subject: efi/arm: Revert deferred unmap of early memmap mapping Commit: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT") deferred the unmap of the early mapping of the UEFI memory map to accommodate the ACPI BGRT code, which looks up the memory type that backs the BGRT table to validate it against the requirements of the UEFI spec. Unfortunately, this causes problems on ARM, which does not permit early mappings to persist after paging_init() is called, resulting in a WARN() splat. Since we don't support the BGRT table on ARM anway, let's revert ARM to the old behaviour, which is to take down the early mapping at the end of efi_init(). Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory ...") Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/arm-init.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/firmware/efi/arm-init.c') diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c index 388a929baf95..1a6a77df8a5e 100644 --- a/drivers/firmware/efi/arm-init.c +++ b/drivers/firmware/efi/arm-init.c @@ -265,6 +265,10 @@ void __init efi_init(void) (params.mmap & ~PAGE_MASK))); init_screen_info(); + + /* ARM does not permit early mappings to persist across paging_init() */ + if (IS_ENABLED(CONFIG_ARM)) + efi_memmap_unmap(); } static int __init register_gop_device(void) -- cgit