Re: [tip:efi/core] efibc: Add EFI Bootloader Control module

From: Ingo Molnar
Date: Fri Apr 29 2016 - 05:54:14 EST



* tip-bot for Compostella, Jeremy <tipbot@xxxxxxxxx> wrote:

> Commit-ID: 06f7d4a1618dbb086e738c93cd1ef416ab01027d
> Gitweb: http://git.kernel.org/tip/06f7d4a1618dbb086e738c93cd1ef416ab01027d
> Author: Compostella, Jeremy <jeremy.compostella@xxxxxxxxx>
> AuthorDate: Mon, 25 Apr 2016 21:06:57 +0100
> Committer: Ingo Molnar <mingo@xxxxxxxxxx>
> CommitDate: Thu, 28 Apr 2016 11:34:02 +0200
>
> efibc: Add EFI Bootloader Control module
>
> This module installs a reboot callback, such that if reboot() is invoked
> with a string argument NNN, "NNN" is copied to the "LoaderEntryOneShot"
> EFI variable, to be read by the bootloader.

> drivers/firmware/efi/Kconfig | 15 +++++++
> drivers/firmware/efi/Makefile | 1 +
> drivers/firmware/efi/efibc.c | 101 ++++++++++++++++++++++++++++++++++++++++++
> include/linux/efi.h | 4 ++
> 4 files changed, 121 insertions(+)

So this bloated things a bit on 32-bit x86 allyesconfig kernels, we now have this
new warning:

drivers/firmware/efi/efibc.c:53:1: warning: the frame size of 2256 bytes is larger than 1024 bytes [-Wframe-larger-than=]

2K of stack use for a function is quite excessive, can we improve the stack
footprint of this code?

Thanks,

Ingo