Re: [PATCH 3/4] x86, efi: Add an efi= kernel command line parameter

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

 



On Thu, Jun 06, 2013 at 10:07:05PM +0200, Borislav Petkov wrote:
> On Thu, Jun 06, 2013 at 08:54:50PM +0100, Matthew Garrett wrote:
> > We want both to be available when we're making the call, but I think
> > we should probably enter via the high addresses. The only reason we're
> > doing this at all is that some systems don't update all of their
> > pointers from physical mode, and we'd prefer them to work rather than
> > fault...
> 
> Actually, we do the 1:1 thing so that EFI runtime works in a kexec
> kernel too. Which won't work if we use the high addresses.

kexec seems like a lower priority than compatibility. Perhaps keep the 
efi argument for people who want to use kexec? hpa suggested allocating 
a fixed high area for UEFI mappings, which would also solve this.

> However, if we can use the 1:1 map *after* SetVirtualAddressMap() has
> been called with the high mappings, then my issue is solved - we drop
> to using 1:1 in the kexec kernel only. But I don't think that is the
> case...

Yeah, calling SetVirtualAddressMap() with high addresses is going to 
result in the firmware having a bunch of pointers to high addresses.

-- 
Matthew Garrett | mjg59@xxxxxxxxxxxxx
--
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