[coreboot] When does AMD release the fam15 spectre microcode updates?

[Rudolf Marek]

Hi,

I found new microcode here [1], I used cpu00610F01_ver0600111F_2018-03-05_AC55EB96.bin as a microcode for my Trinity family15h CPU.
I hacked together a new microcode header which contains the equivalence table etc to be able to load this microcode into the CPU from Linux.

dd if=/lib/firmware/amd-ucode/microcode_amd_fam15h.bin bs=1 count=84 of=header.bin
cat header.bin cpu00610F01_ver0600111F_2018-03-05_AC55EB96.bin > microcode_amd_fam15h.bin

copy the file to same location and trigger update:

echo 1 >  /sys/devices/system/cpu/microcode/reload

[ 6032.948243] microcode: CPU0: new patch_level=0x0600111f
[ 6032.964913] microcode: CPU2: new patch_level=0x0600111f

Please note that the header.bin does contain a size of the microcode blob, but it happens to be the same, so it works. Normally the container
may contain more microcode blobs. But in my case I use just "right" one for my CPU.

The new microcode seems to be adding the IBPB feature.

Thanks
Rudolf


[1] https://github.com/platomav/CPUMicrocodes