[coreboot] memtest86 reading 0k memory

[Jonathan A. Kollasch]

On Thu, Feb 05, 2015 at 12:23:40PM -0600, Timothy Pearson wrote:
> All,
> 
> I have a board here that loads memtest86 but won't actually test memory.
> 
> This is the output:
> 
>       Memtest86+ v2.11
> AMD K10 CPU @ 2312 MHz
> L1 Cache:   64K  35028 MB/s
> L2 Cache:  512K   6963 MB/s
> L3 Cache: 2048K   6052 MB/s
> Memory  :    0K |-------------------------------------------------
> Chipset :
> 
> 
> 
> 
>                          0K  LinuxBIOS
> 
> 
> 
> I'm guessing memtest86 doesn't understand coreboot's memory
> tables/structure, but I have no idea why that would be.  The e820
> map is valid:
> e820: BIOS-provided physical RAM map:
> BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
> BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
> BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
> BIOS-e820: [mem 0x0000000000100000-0x000000003ffacfff] usable
> BIOS-e820: [mem 0x000000003ffad000-0x000000003fffffff] reserved
> BIOS-e820: [mem 0x00000000e0000000-0x00000000efffffff] reserved
> 
> Any ideas?  Other than this one irritating glitch coreboot is
> working perfectly on this board.

That's a pretty old memtest86+.  Also, memtest86+ prefers
linuxbios/coreboot memory map to e820.  This becomes a problem
when SeaBIOS sets up a USB controller to DMA to e820-reserved
memory that wasn't reserved by coreboot.

Try a modern memtest86+ with the coreboot table probe patched out.

	Jonathan Kollasch