Builtin early microcode breaks s2ram v4.6-rcX

From: Jim Bos
Date: Sun May 15 2016 - 08:16:41 EST



As I noticed microcode was no longer being loaded on v4.6-rcX I switched
to builtin microcode as described in

Documentation/x86/early-microcode.txt

So I have now this:
CONFIG_FW_LOADER=y
CONFIG_FIRMWARE_IN_KERNEL=y
CONFIG_EXTRA_FIRMWARE="intel-ucode/06-2a-07 radeon/REDWOOD_me.bin
radeon/REDWOOD_pfp.bin radeon/REDWOOD_rlc.bin radeon/REDWOOD_smc.bin
radeon/CYPRESS_uvd.bin"
CONFIG_EXTRA_FIRMWARE_DIR="/lib/firmware"
# CONFIG_FW_LOADER_USER_HELPER_FALLBACK is not set

That works, i.e. when booting as very first line I get message microcode
is loaded, see attached dmesg

However, after suspend to ram, trying to resume results in total lockup
of the machine: no ping, no sysrq-keys, only hard reset works.

Trying to bisect this didn't really work, earlier kernel (v4.5) doesn't
even boot with this config.

I'm seeing this on 2 rather different machines, on intel quadcore on 2-3
year old mobo and a dual core pentium on fairly new mobo.
Note that both machines do boot using EFI.

_
Jim


Attachment: dmesg.gz
Description: application/gzip