Commit Graph

12 Commits

Author SHA1 Message Date
Linus Torvalds
8ca038dc10 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI updates from Ingo Molnar:
 "This patchset makes changes to the bzImage EFI header, so that it can
  be signed with a secure boot signature tool.  It should not affect
  anyone who is not using the EFI self-boot feature in any way."

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, efi: Fix NumberOfRvaAndSizes field in PE32 header for EFI_STUB
  x86, efi: Fix .text section overlapping image header for EFI_STUB
  x86, efi: Fix issue of overlapping .reloc section for EFI_STUB
2012-05-23 10:40:34 -07:00
Matt Fleming
b1994304fc x86, efi: Add dedicated EFI stub entry point
The method used to work out whether we were booted by EFI firmware or
via a boot loader is broken. Because efi_main() is always executed
when booting from a boot loader we will dereference invalid pointers
either on the stack (CONFIG_X86_32) or contained in %rdx
(CONFIG_X86_64) when searching for an EFI System Table signature.

Instead of dereferencing these invalid system table pointers, add a
new entry point that is only used when booting from EFI firmware, when
we know the pointer arguments will be valid. With this change legacy
boot loaders will no longer execute efi_main(), but will instead skip
EFI stub initialisation completely.

[ hpa: Marking this for urgent/stable since it is a regression when
  the option is enabled; without the option the patch has no effect ]

Signed-off-by: Matt Fleming <matt.hfleming@intel.com>
Link: http://lkml.kernel.org/r/1334584744.26997.14.camel@mfleming-mobl1.ger.corp.intel.com
Reported-by: Jordan Justen <jordan.l.justen@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> v3.3
2012-04-16 11:41:44 -07:00
H. Peter Anvin
a9aff3eaaf Merge branch x86/build into x86/efi and fix up arch/x86/boot/tools/build.c
Reason for merge:
       The updates to the EFI boot stub generation conflicted with the
       changes to properly use the get/put_unaligned_le*() macros to
       generate images.

       This merge commit completes the conversion in
       arch/x86/boot/tools/build.c including the places in the code
       which had been changed on the x86/efi branch.

Resolved Conflicts:
	arch/x86/boot/tools/build.c

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-03-28 13:11:36 -07:00
Matt Fleming
e31be363df x86, efi: Fix .text section overlapping image header for EFI_STUB
This change modifes the PE .text section to start after
the first sector of the kernel image.

The header may be modified by the UEFI secure boot signing,
so it is not appropriate for it to be included in one of the
image sections. Since the sections are part of the secure
boot hash, this modification to the .text section contents
would invalidate the secure boot signed hash.

Note: UEFI secure boot does hash the image header, but
fields that are changed by the signing process are excluded
from the hash calculation.  This exclusion process is only
handled for the image header, and not image sections.

Luckily, we can still easily boot without the first sector
by initializing a few fields in arch/x86/boot/compressed/eboot.c.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1332520506-6472-3-git-send-email-jordan.l.justen@intel.com
[jordan.l.justen@intel.com: set .text vma & file offset]
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-03-26 13:10:01 -07:00
H. Peter Anvin
a51f404775 x86, build: Fix portability issues when cross-building
It would appear that we never actually generated a correct CRC when
building on a bigendian machine.  Depending on the word size, we would
either generate an all-zero CRC (64-bit machine) or a byte-swapped
CRC (32-bit machine.)  Fix the types used so we don't arbitrarily use
a 64-bit word to hold 32-bit numbers, and pass the CRC through
put_unaligned_le32() like all the other numbers.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Bowler <nbowler@elliptictech.com>
Link: http://lkml.kernel.org/r/20120229111322.9eb4b23ff1672e8853ad3b3b@canb.auug.org.au
2012-02-28 23:40:56 -08:00
H. Peter Anvin
b8d43cb504 x86, tools: Remove unneeded header files from tools/build.c
We include <sys/sysmacros.h> and <asm/boot.h>, but none of those
header files actually provide anything this file needs.  Furthermore,
it breaks cross-compilation, so just remove them.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Bowler <nbowler@elliptictech.com>
Link: http://lkml.kernel.org/r/20120229111322.9eb4b23ff1672e8853ad3b3b@canb.auug.org.au
2012-02-28 23:40:15 -08:00
Matt Fleming
92f42c50f2 x86, efi: Fix endian issues and unaligned accesses
We may need to convert the endianness of the data we read from/write
to 'buf', so let's use {get,put}_unaligned_le32() to do that. Failure
to do so can result in accessing invalid memory, leading to a
segfault.  Stephen Rothwell noticed this bug while cross-building an
x86_64 allmodconfig kernel on PowerPC.

We need to read from and write to 'buf' a byte at a time otherwise
it's possible we'll perform an unaligned access, which can lead to bus
errors when cross-building an x86 kernel on risc architectures.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Bowler <nbowler@elliptictech.com>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-6-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-28 10:23:02 -08:00
Matt Fleming
291f36325f x86, efi: EFI boot stub support
There is currently a large divide between kernel development and the
development of EFI boot loaders. The idea behind this patch is to give
the kernel developers full control over the EFI boot process. As
H. Peter Anvin put it,

"The 'kernel carries its own stub' approach been very successful in
dealing with BIOS, and would make a lot of sense to me for EFI as
well."

This patch introduces an EFI boot stub that allows an x86 bzImage to
be loaded and executed by EFI firmware. The bzImage appears to the
firmware as an EFI application. Luckily there are enough free bits
within the bzImage header so that it can masquerade as an EFI
application, thereby coercing the EFI firmware into loading it and
jumping to its entry point. The beauty of this masquerading approach
is that both BIOS and EFI boot loaders can still load and run the same
bzImage, thereby allowing a single kernel image to work in any boot
environment.

The EFI boot stub supports multiple initrds, but they must exist on
the same partition as the bzImage. Command-line arguments for the
kernel can be appended after the bzImage name when run from the EFI
shell, e.g.

Shell> bzImage console=ttyS0 root=/dev/sdb initrd=initrd.img

v7:
 - Fix checkpatch warnings.

v6:

 - Try to allocate initrd memory just below hdr->inird_addr_max.

v5:

 - load_options_size is UTF-16, which needs dividing by 2 to convert
   to the corresponding ASCII size.

v4:

 - Don't read more than image->load_options_size

v3:

 - Fix following warnings when compiling CONFIG_EFI_STUB=n

   arch/x86/boot/tools/build.c: In function ‘main’:
   arch/x86/boot/tools/build.c:138:24: warning: unused variable ‘pe_header’
   arch/x86/boot/tools/build.c:138:15: warning: unused variable ‘file_sz’

 - As reported by Matthew Garrett, some Apple machines have GOPs that
   don't have hardware attached. We need to weed these out by
   searching for ones that handle the PCIIO protocol.

 - Don't allocate memory if no initrds are on cmdline
 - Don't trust image->load_options_size

Maarten Lankhorst noted:
 - Don't strip first argument when booted from efibootmgr
 - Don't allocate too much memory for cmdline
 - Don't update cmdline_size, the kernel considers it read-only
 - Don't accept '\n' for initrd names

v2:

 - File alignment was too large, was 8192 should be 512. Reported by
   Maarten Lankhorst on LKML.
 - Added UGA support for graphics
 - Use VIDEO_TYPE_EFI instead of hard-coded number.
 - Move linelength assignment until after we've assigned depth
 - Dynamically fill out AddressOfEntryPoint in tools/build.c
 - Don't use magic number for GDT/TSS stuff. Requested by Andi Kleen
 - The bzImage may need to be relocated as it may have been loaded at
   a high address address by the firmware. This was required to get my
   macbook booting because the firmware loaded it at 0x7cxxxxxx, which
   triggers this error in decompress_kernel(),

	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
		error("Destination address too large");

Cc: Mike Waychison <mikew@google.com>
Cc: Matthew Garrett <mjg@redhat.com>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1321383097.2657.9.camel@mfleming-mobl1.ger.corp.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-12 14:26:10 -08:00
Michal Marek
079f85e624 x86, build: Do not set the root_dev field in bzImage
This has been obsoleted by the root= commandline and the rdev utility
for many, many years.  People who still depend on this will surely
have a copy of the rdev utility around, the rest of the world gets rid
of another piece of buildhost-dependent data in the build. Thanks to
Paul Bolle for the build.c cleanup.

Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Link: http://lkml.kernel.org/r/1302607824-24699-1-git-send-email-mmarek@suse.cz
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-25 12:46:05 -07:00
H. Peter Anvin
5e47c478b0 x86: remove zImage support
Impact: obsolete feature removal

The zImage kernel format has been functionally unused for a very long
time.  It is just barely possible to build a modern kernel that still
fits within the zImage size limit, but it is highly unlikely that
anyone ever uses it.  Furthermore, although it is still supported by
most bootloaders, it has been at best poorly tested (or not tested at
all); some bootloaders are even known to not support zImage at all and
not having even noticed.

Also remove some really obsolete constants that no longer have any
meaning.

LKML-Reference: <49B703D4.1000008@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-11 11:00:00 -07:00
Ian Campbell
7d6e737c8d x86: add a crc32 checksum to the kernel image.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 17:40:46 +02:00
Thomas Gleixner
19d8d79ccf i386: move boot
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11 11:16:41 +02:00