Arch Linux

hotvic

Member

Registered: 2013-02-11

Posts: 109

EFI's CSM and Kernel conflict ?

There's chance to have a conflict between CSM (Compatibility Support Module) and Linux Kernel ?

I'm asking this because when "Launch CSM" is set to "Always" in EFI setup, kernel simply won't boot doesn't show error or anything.

Let me explain better and get in details,

• First I went to EFI setup page (BIOS settings is wrong, right ?) with tuning some options in mind, after change some options saved and then rebooted.

• Then gummiboot booted normal as usual, but after selecting the Linux (Arch; uksm-ck, and after core too) screen simply goes black instantly and nothing happened after that.

• Just for joke I rebooted again and from gummiboot menu selected Windows Boot Manager and for my surprise it boots up normally and correctly.

• I went to EFI setup page again trying to find what options caused Linux Kernel to not boot.
  So from here I do just like that: change one setting; save; reboot; won't work, change back, change other setting; reboot; and try again.
  So in this loop I come to CSM setup page, I don't use it then I think "why load this if do not use this sh**t" so I set "Launch CSM" to "Never", and continues the loop, reboot, try to boot, to my surprise it Linux Kernel boots up normal no error anything.

So some EFI setting (I don't know which is yet ) plus "Launch CSM" set to yes cause Linux Kernel to not boot.

Why this thread instead of a bug report ? I don't have sufficient info to make a bug report and I'm not sure what's this exactly, so decided to post here and see your opinions