diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-03-19 09:47:30 +0100 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-03-19 09:47:30 +0100 |
commit | 0d4a42f6bd298e826620585e766a154ab460617a (patch) | |
tree | 406d8f7778691d858dbe3e48e4bbb10e99c0a58a /arch/x86/include/asm/bootparam_utils.h | |
parent | d62b4892f3d9f7dd2002e5309be10719d6805b0f (diff) | |
parent | a937536b868b8369b98967929045f1df54234323 (diff) |
Merge tag 'v3.9-rc3' into drm-intel-next-queued
Backmerge so that I can merge Imre Deak's coalesced sg entries fixes,
which depend upon the new for_each_sg_page introduce in
commit a321e91b6d73ed011ffceed384c40d2785cf723b
Author: Imre Deak <imre.deak@intel.com>
Date: Wed Feb 27 17:02:56 2013 -0800
lib/scatterlist: add simple page iterator
The merge itself is just two trivial conflicts:
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'arch/x86/include/asm/bootparam_utils.h')
-rw-r--r-- | arch/x86/include/asm/bootparam_utils.h | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/arch/x86/include/asm/bootparam_utils.h b/arch/x86/include/asm/bootparam_utils.h new file mode 100644 index 000000000000..653668d140f9 --- /dev/null +++ b/arch/x86/include/asm/bootparam_utils.h @@ -0,0 +1,54 @@ +#ifndef _ASM_X86_BOOTPARAM_UTILS_H +#define _ASM_X86_BOOTPARAM_UTILS_H + +#include <asm/bootparam.h> + +/* + * This file is included from multiple environments. Do not + * add completing #includes to make it standalone. + */ + +/* + * Deal with bootloaders which fail to initialize unknown fields in + * boot_params to zero. The list fields in this list are taken from + * analysis of kexec-tools; if other broken bootloaders initialize a + * different set of fields we will need to figure out how to disambiguate. + * + * Note: efi_info is commonly left uninitialized, but that field has a + * private magic, so it is better to leave it unchanged. + */ +static void sanitize_boot_params(struct boot_params *boot_params) +{ + /* + * IMPORTANT NOTE TO BOOTLOADER AUTHORS: do not simply clear + * this field. The purpose of this field is to guarantee + * compliance with the x86 boot spec located in + * Documentation/x86/boot.txt . That spec says that the + * *whole* structure should be cleared, after which only the + * portion defined by struct setup_header (boot_params->hdr) + * should be copied in. + * + * If you're having an issue because the sentinel is set, you + * need to change the whole structure to be cleared, not this + * (or any other) individual field, or you will soon have + * problems again. + */ + if (boot_params->sentinel) { + /* fields in boot_params are left uninitialized, clear them */ + memset(&boot_params->olpc_ofw_header, 0, + (char *)&boot_params->efi_info - + (char *)&boot_params->olpc_ofw_header); + memset(&boot_params->kbd_status, 0, + (char *)&boot_params->hdr - + (char *)&boot_params->kbd_status); + memset(&boot_params->_pad7[0], 0, + (char *)&boot_params->edd_mbr_sig_buffer[0] - + (char *)&boot_params->_pad7[0]); + memset(&boot_params->_pad8[0], 0, + (char *)&boot_params->eddbuf[0] - + (char *)&boot_params->_pad8[0]); + memset(&boot_params->_pad9[0], 0, sizeof(boot_params->_pad9)); + } +} + +#endif /* _ASM_X86_BOOTPARAM_UTILS_H */ |