Re: Linux 2.6.27-rc5: System boot regression caused by commit a2bd7274b47124d2fc4dfdb8c0591f545ba749dd

Linus Torvalds
2008-08-31T03:59:56Z

On Sat, 30 Aug 2008, Yinghai Lu wrote:
>
> then
> 1. we should not probe them in probe.c
> 2. at least we should not try to request_resource for them in
> pcibios_resource_survey...
>
> just pretend that they are not existing.

You are missing the fact that we need to know where existing resources
are, even if we can't do anything about them!

Read my explanation from yesterday about why we need to add the e820
resources to the resource map in the first place.

Short recap:

- we need to populate the resource map with as much possible information
about the system as we can..

- .. because when we assign _dynamic_ resources, we need to make sure
that they don't clash with random system resources that we don't really
otherwise have a lot of visibility into.

So the resource tree is not just about resources we control, it's also
about resources that others control(led) and we don't necessarily know a
lot about.

Linus