Re: [edk2] Corrupted EFI region

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



[ Readding Matthew Garrett to the Cc list, seeing as we both got removed
  for some unknown reason ]

On Wed, 07 Aug, at 10:23:56AM, Andrew Fish wrote:

> OK so I think I need some Cliff Notes here to help me understand what
> is going on...
> 
> type 4 is EfiBootServicesData and attr 0x0f is cache attributes with
> no request for a runtime mapping. This is not runtime memory so to the
> OS loader it is just memory EFI has used that will get freed back to
> the OS after ExitBootServices(), along with EfiBootServicesCode,
> EfiLoaderCode, and EfiLoaderData. The EfiLoaderCode and EfiLoaderData
> also get freed back to the OS and they just exist for the convenience
> of the OS loader. 
> 
> So I can't figure out why this maters? Given:

We've seen a bunch of systems that make calls into EfiBootServicesCode
after ExitBootServices(). There were some Apple machines in that list,
though I don't have the details but Matthew should.
 
So we map these regions unconditionally and in their original state,
otherwise the firmware will generate fatal page faults when trying to
access those memory regions.

-- 
Matt Fleming, Intel Open Source Technology Center
--
To unsubscribe from this list: send the line "unsubscribe linux-efi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux