> Date: Sat, 23 Apr 2016 13:23:49 +0200 (CEST)
> From: Mark Kettenis <mark.kette...@xs4all.nl>
>
> > Date: Sat, 23 Apr 2016 12:49:25 +0200 (CEST)
> > From: Mark Kettenis <mark.kette...@xs4all.nl>
> >
> > > Could it be this problem is related to
> > > sys/arch/amd64/stand/efi/include/i386/efibind.h using sys/stdint.h
> > > which looks like it will make uint64_t unsigned long on for BOOTIA32.EFI
> > > not unsigned long long?
> >
> > We consistently define uint64_t as unsigned long long (unlike some
> > other OSes) so this shouldn't be the case.
> >
> > I didn't look in detail at the report yet, but I can confirm that I
> > had a similar problem on the Asus x205ta. I worked around it by
> > nuking the GPT and using a traditional MBR partition table instead.
> > Never got around investigating the issue any further.
>
> Seems that this is a structure memberalignment issue:
>
> For BOOTX64 we have:
>
> (gdb) print &((EFI_BLOCK_IO_MEDIA *)0)->LastBlock
> $1 = (EFI_LBA *) 0x18
>
> wheras for BOTIA32 we get:
>
> (gdb) print &((EFI_BLOCK_IO_MEDIA *)0)->LastBlock
> $1 = (EFI_LBA *) 0x14
>
> Looking at the struct definition:
>
> typedef struct {
> UINT32 MediaId;
> BOOLEAN RemovableMedia;
> BOOLEAN MediaPresent;
>
> BOOLEAN LogicalPartition;
> BOOLEAN ReadOnly;
> BOOLEAN WriteCaching;
>
> UINT32 BlockSize;
> UINT32 IoAlign;
>
> EFI_LBA LastBlock;
> } EFI_BLOCK_IO_MEDIA;
>
> We see that the 64-bit code has padding between IoAlign and LastBlock
> to make sure that LastBlock is properly aligned. That padding isn't
> there in the 32-bit code since the System V ABI doesn't require 64-bit
> alignment here. But I guess the 32-bit Windows ABI does.
And here is a possible fix. Got the inspiration from the SYSLINUX
bootloader. This forces alignment of the EFI-specific 64-bit types.
It leaves the normal int64_t/uint64_t alone, but we shouldn't use
those directly to define EFI data structures.
John, can you confirm that this fixes the issue for you?
Jonathan, Ken, provided that it does, ok?
Index: efi/include/i386/efibind.h
===================================================================
RCS file: /home/cvs/src/sys/arch/amd64/stand/efi/include/i386/efibind.h,v
retrieving revision 1.2
diff -u -p -r1.2 efibind.h
--- efi/include/i386/efibind.h 11 Dec 2015 20:17:10 -0000 1.2
+++ efi/include/i386/efibind.h 23 Apr 2016 11:38:26 -0000
@@ -88,8 +88,8 @@ Revision History
#ifndef ACPI_THREAD_ID /* ACPI's definitions are fine, use those */
#define ACPI_USE_SYSTEM_INTTYPES 1 /* Tell ACPI we've defined types */
-typedef uint64_t UINT64;
-typedef int64_t INT64;
+typedef uint64_t UINT64 __attribute__((__aligned__(8)));
+typedef int64_t INT64 __attribute__((__aligned__(8)));
#ifndef _BASETSD_H_
typedef uint32_t UINT32;
