coreboot's memtest86+ payload is buggy compared to memtest86+ floppy (which could be downloaded from memtest.org and added to CBFS to be accessible as SeaBIOS menu entry). at AMD Lenovo G505S and maybe some other coreboot laptops, the USB devices like keyboard are not working at coreboot's memtest86+ while working fine at all the other payloads using "libpayload" (i.e. coreinfo or tint) - so it's not a libpayload problem - and also the same USB keyboards are working at memtest86+ floppy. So it is obvious something is broken at 86+ payload source code.
Also, with LZMA compression 86+ floppy occupies much less space than 86+ payload. So, aside from academic/research purposes, I do not see any advantages of 86+ payload compared to 86+ floppy - only disadvantages: larger size and troubled USB. I've seriously considered submitting a patch which replaces coreboot's memtest86+ payload with a floppy (download, compare its' checksum and then insert to CBFS), but then I thought that maybe someone could need 86+ payload as a coding example.
If you would like to try out a floppy (e.g. because something else - like 2GB support - could be also broken at 86+ payload, while working fine at 86+ floppy booted through SeaBIOS) , here are the instructions:
1) Download the latest 5.01 version of memtest86+ from memtest86.org :
wget https://www.memtest.org/download/5.01/memtest86+-5.01.floppy.zip
2) Calculate its' sha256 :
sha256sum ./memtest86+-5.01.floppy.zip
should be
2a2d4c1234c9130e1da5fea941ccfbaa343739d5b3302b5f3f9b24077868f8ee ./memtest86+-5.01.floppy.zip
3) If sha256 is correct, unzip ./memtest86+-5.01.floppy.zip . You'll get a "floppy" directory with these files: ls ./floppy/ dd.exe install64.bat install.bat memtestp.bin rawrite.exe README.txt You only need memtestp.bin , sha256 of which is " ddd4a2ba44c312aa4f2c7506a388cc2ca7f1caec60c3c6d80ed8a9f0b43d529c "
4) Size of memtestp.bin file is 150024 bytes. To be understood by SeaBIOS, it needs to be expanded to 1474560 bytes (by zeroes), which could be done with this command:
dd if=/dev/zero of=./memtestp.bin bs=1 count=1 seek=1474559 conv=notrunc
sha256 of expanded memtestp.bin file will be " 364535abd0d105da9396df6015e480c4d4c52b07dcc4e1d4756bde8ef87a30f1 "
5) Now it could be added to the compiled coreboot.rom with this command:
./build/cbfstool ./build/coreboot.rom add -f ./floppy/memtestp.bin -n floppyimg/memtestp.lzma -t raw -c lzma
If done everything correctly, it will be available at SeaBIOS boot menu as Ramdisk [memtestp]
Best regards, Mike Banon
On Mon, Nov 5, 2018 at 3:51 PM Krystian Hebel krystian.hebel@3mdeb.com wrote:
On 11/05/18 13:32, Paul Menzel wrote:
Thank you for the patch. If it’s the common problem, then it was > fixed in “coreboot’s” MemTest86+ [1]. Can you reproduce the problem > with that version?
Yes, it is the version on which I tested. It worked OK before [1], because when no coreboot tables were found MemTest86+ resorted to e820.
It was reproduced on PC Engines apu3 (2 GB version) and apu1, the latter requires SPD fix [2]. 4 GB versions of apu doesn't seem to be affected.
Regards,
Krystian
SeaBIOS mailing list SeaBIOS@seabios.org https://mail.coreboot.org/mailman/listinfo/seabios