Garrett: Booting with EFI

Posted Jul 15, 2011 2:20 UTC (Fri) by mjg59 (subscriber, #23239)
In reply to: Garrett: Booting with EFI by pjones
Parent article: Garrett: Booting with EFI

...and the problem is, obviously, to a large extent influenced by a specification that explicitly allows this kind of behaviour while later on disclaiming any responsibility for how operating systems should handle it. The only way to handle that is by having more participation in the appropriate bodies.

Garrett: Booting with EFI

Posted Jul 15, 2011 4:04 UTC (Fri) by ringerc (subscriber, #3071) [Link] (9 responses)

It sounds like EFI also needs a better test suite. Don't just boot Windows, boot the EFI test suite image. Require that vendors that claim "EFI support" pass the test suite.

If a test suite that checks for all these quirks can be grown over time as issues are discovered, and if there's an incentive for vendors to actually use the test suite, then things might improve. It's not too late in the implementation of EFI to get that sort of thing moving.

Garrett: Booting with EFI

Posted Jul 15, 2011 13:39 UTC (Fri) by pjones (subscriber, #31722) [Link] (8 responses)

It actually does have this.

Garrett: Booting with EFI

Posted Jul 15, 2011 15:01 UTC (Fri) by hitmark (guest, #34609) [Link] (7 responses)

Let me guess, MS has their own test suite...

Garrett: Booting with EFI

Posted Jul 15, 2011 17:04 UTC (Fri) by pjones (subscriber, #31722) [Link]

Not that I know of. As far as I know they use the SCT on uefi.org just like everybody else does.

There really isn't anything obviously nefarious going on here.

Garrett: Booting with EFI

Posted Jul 15, 2011 17:27 UTC (Fri) by mjg59 (subscriber, #23239) [Link] (5 responses)

The problem is actually that none of the bugs we've hit are in paths exercised by the test suite, either because it doesn't test them or because they only trigger once you've set up non-executable pages or non-1:1 pagetables.

Garrett: Booting with EFI

Posted Jul 15, 2011 18:05 UTC (Fri) by cesarb (subscriber, #6266) [Link] (1 responses)

Would it be possible to have them enhance the test suite to catch these kinds of problems?

Garrett: Booting with EFI

Posted Jul 15, 2011 20:24 UTC (Fri) by pjones (subscriber, #31722) [Link]

That's something I'm looking into for the future, but for various reasons hasn't happened yet.

Garrett: Booting with EFI

Posted Jul 15, 2011 18:10 UTC (Fri) by luto (guest, #39314) [Link] (2 responses)

Does the test suite not include things like "intelligently handles the boot menu?"

It would be fairly easy to test. Just put three bootloaders in the system partition: EFI/boot/bootx64.efi, EFI/test/a.efi, and EFI/test/b.efi. Set a.efi first in the boot order and b.efi second. Then tell the user running the test to navigate their firmware menu and boot from b.efi.

Sadly, even my shiny new Intel board can't do that. You'd think that the inventor of the original EFI spec would get this right. (Of course, the board can't reboot via EFI either. Oh, well.)

Garrett: Booting with EFI

Posted Jul 15, 2011 18:13 UTC (Fri) by mjg59 (subscriber, #23239) [Link]

No, because it's simply an application that runs under the EFI shell.

Garrett: Booting with EFI

Posted Jul 20, 2011 1:14 UTC (Wed) by pjones (subscriber, #31722) [Link]

In addition to what Matthew said, the boot menu is also not standardized. I think there's some chance we can script some boot menus, if they're compliant with the HII guidelines, but some of them are simply outside the realm of possibility.