This reverts commit 793423cf07e51e3185b8680167115813589c057d.

The 64-bit alignment affects the size of efi_config_table_32_t,
which is used as an array type. On the other hand, the former
byte alignment could trigger alignment faults during firmware
calls on 32-bit ARM, since UEFI defines efi_guid_t as a struct
of UINT32 + UINT16 + UINT16 + UINT8[8], and so it may use load/
store multiple instructions [requiring 32-bit alignment], e.g.,
on GUID pointers passed as function arguments since UEFI's view
of the type has implicit 32-bit alignment.

Let's sort this out for the next release, and revert the change
for now.

Fixes: 793423cf07e5 ("efi: Align 'efi_guid_t' to 64 bits")
Reported-by: Heinrich Schuchardt <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Qian Cai <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
---
 include/linux/efi.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/efi.h b/include/linux/efi.h
index e6480c805932..100ce4a4aff6 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -48,7 +48,7 @@ typedef u16 efi_char16_t;             /* UNICODE character */
 typedef u64 efi_physical_addr_t;
 typedef void *efi_handle_t;
 
-typedef guid_t efi_guid_t __aligned(8);
+typedef guid_t efi_guid_t;
 
 #define EFI_GUID(a,b,c,d0,d1,d2,d3,d4,d5,d6,d7) \
        GUID_INIT(a, b, c, d0, d1, d2, d3, d4, d5, d6, d7)
-- 
2.19.2

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