Re: [GIT PULL] EFI urgent fixes

[Ingo Molnar <mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

* Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> wrote:

> Folks, please pull the following fixes. The revert addresses a
> regression that Ard hit when booting Qemu and Xen, and the other patch
> ensures that we don't triple fault when receiving an NMI or MCE during
> an EFI mixed mode call, which may happen, for instance, when running
> perf.
> 
> The pull is against tip/x86/efi because tip/x86/urgent doesn't contain
> commit d1a8d66b9177 ("efi/libstub: Call get_memory_map() to obtain map
> and desc sizes") needed for the revert.
> 
> If you'd prefer for me to resend this after the merge window closes,
> just let me know.
> 
> The following changes since commit 3c01b74e818a7a3b2ee9b0d584cca0bc154a031c:
> 
>   Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi (2015-01-29 19:16:40 +0100)
> 
> are available in the git repository at:
> 
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git tags/efi-urgent
> 
> for you to fetch changes up to 43a9f69692b232d1c64c913a27507eb14a1c47fd:
> 
>   Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes" (2015-02-18 11:38:13 +0000)
> 
> ----------------------------------------------------------------
>  * Leave a valid 64-bit IDT installed during runtime EFI mixed mode
>    calls to avoid triple faults if an NMI/MCE is received.
> 
>  * Revert Ard's change to the libstub get_memory_map() that went into
>    the v3.20 merge window because it causes boot regressions on Qemu and
>    Xen.
> 
> ----------------------------------------------------------------
> Matt Fleming (2):
>       x86/efi: Avoid triple faults during EFI mixed mode calls
>       Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes"
> 
>  arch/x86/boot/compressed/Makefile              |   1 +
>  arch/x86/boot/compressed/efi_stub_64.S         |  25 ----
>  arch/x86/boot/compressed/efi_thunk_64.S        | 196 +++++++++++++++++++++++++
>  arch/x86/platform/efi/efi_stub_64.S            | 161 --------------------
>  arch/x86/platform/efi/efi_thunk_64.S           | 121 ++++++++++++---
>  drivers/firmware/efi/libstub/efi-stub-helper.c |  16 +-
>  6 files changed, 307 insertions(+), 213 deletions(-)
>  create mode 100644 arch/x86/boot/compressed/efi_thunk_64.S

Pulled, thanks Matt!

Btw., I find the revert a bit sad: in most cases breaking 
virtualized environments isn't a regression really, it's 
_them_ who couple to the kernel in an incestuous way that 
causes the problem: fixes should come from them ...

Thanks,

	Ingo