Re: [PATCH v2] x86: Add a list for custom page fault handlers.

[Ingo Molnar <mingo@elte.hu>]

* Pekka Paalanen <pq@iki.fi> wrote:

> I have two reasons why I'd like to let it be a module:
> - it's "broken", the relay buffers are cleared on module unload
> - it's a lot easier to push updated version for testing to people
> 
> Ok, the first one is just a silly excuse, but the second one is to 
> avoid forcing non-developer users to patch their kernels. This is a 
> much needed tool for the Nouveau project even in it's current form.

i dont think this second problem is a practical one: i've test-merged 
mmiotrace two days ago into x86.git and it's holding up very well in my 
testing (it has not caused a single hickup so far). It's nice optional 
debug functionality and i dont see any reason why not to merge it.

a few cleanup requests:

- please make the pagefault callbacks explicit as Arjan has asked

- any reason why it lives in arch/x86/kernel/mmiotrace/? It should be a
  prime-time member of arch/x86/mm/ i think.

- please make it build-in-able, not modules-only.

- [ longer-term: think about integrating pf_in.c with the x86
    emulator/disassembler of KVM. ]

	Ingo