Pure EFI boot not possible because of missing options in current kernel config
I had many hours of struggle with this problem some time ago - syslinux begins to load the kernel and everything just freezes. Eventually I found the solution, but because it was not that critical back then I didn’t create an issue in the bug tracker. Things changed with my new hardware and now I have no other choice but to use EFI boot so I’m posting my findings and will hope the changes can get into the linux-grsec package.
After many kernel recompilations I found that in order for pure EFI boot to work the frame buffer device support should be build into the kernel (not as a module). It then unlocks another option - CONFIG_FB_EFI (which of course depends on EFI support being enabled but that’s already done in current Alpine config) - which should also be build-in. And that’s it, nothing more, nothing less. I tested it on my two old laptops and in Virtualbox.To sum it up:
CONFIG_FB=m —>CONFIG_FB=y
CONFIG_FB_EFI=y
I’m not sure if these changes in kernel config would affect grsecurity patches (I strongly hope that they will not).
I can provide my test kernel configs but they are for 3.12.38 kernel. You can take a look at current Arch Linux kernel config for the above mentioned options.
(from redmine: issue id 5191, created on 2016-02-25, closed on 2016-12-22)
- Relations:
- relates #5731 (closed)
- Changesets:
- Revision 31b878cc by Timo Teräs on 2016-11-24T09:23:43Z:
main/linux-vanilla: enable rtsx pci and efifb
ref #5191
ref #6486
- Revision 40e4c472 by Timo Teräs on 2016-11-24T09:23:43Z:
main/linux-grsec: enable rtsx pci and efifb
fixes #5191
fixes #6486