linux-toradex.git/arch/x86/boot/Makefile, branch v3.9.2 Linux kernel for Apalis and Colibri modules x86, build: Dynamically find entry points in compressed startup code 2013-01-28T04:19:37+00:00 David Woodhouse David.Woodhouse@intel.com 2013-01-10T14:31:59+00:00 99f857db8857aff691c51302f93648263ed07eb1 We have historically hard-coded entry points in head.S just so it's easy to build the executable/bzImage headers with references to them. Unfortunately, this leads to boot loaders abusing these "known" addresses even when they are *explicitly* told that they "should look at the ELF header to find this address, as it may change in the future". And even when the address in question *has* actually been changed in the past, without fanfare or thought to compatibility. Thus we have bootloaders doing stunningly broken things like jumping to offset 0x200 in the kernel startup code in 64-bit mode, *hoping* that startup_64 is still there (it has moved at least once before). And hoping that it's actually a 64-bit kernel despite the fact that we don't give them any indication of that fact. This patch should hopefully remove the temptation to abuse internal addresses in future, where sternly worded comments have not sufficed. Instead of having hard-coded addresses and saying "please don't abuse these", we actually pull the addresses out of the ELF payload into zoffset.h, and make build.c shove them back into the right places in the bzImage header. Rather than including zoffset.h into build.c and thus having to rebuild the tool for every kernel build, we parse it instead. The parsing code is small and simple. This patch doesn't actually move any of the interesting entry points, so any offending bootloader will still continue to "work" after this patch is applied. For some version of "work" which includes jumping into the compressed payload and crashing, if the bzImage it's given is a 32-bit kernel. No change there then. [ hpa: some of the issues in the description are addressed or retconned by the 2.12 boot protocol. This patch has been edited to only remove fixed addresses that were *not* thus retconned. ] Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Link: http://lkml.kernel.org/r/1358513837.2397.247.camel@shinybook.infradead.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Fleming <matt.fleming@intel.com> 
We have historically hard-coded entry points in head.S just so it's easy
to build the executable/bzImage headers with references to them.

Unfortunately, this leads to boot loaders abusing these "known" addresses
even when they are *explicitly* told that they "should look at the ELF
header to find this address, as it may change in the future". And even
when the address in question *has* actually been changed in the past,
without fanfare or thought to compatibility.

Thus we have bootloaders doing stunningly broken things like jumping
to offset 0x200 in the kernel startup code in 64-bit mode, *hoping*
that startup_64 is still there (it has moved at least once
before). And hoping that it's actually a 64-bit kernel despite the
fact that we don't give them any indication of that fact.

This patch should hopefully remove the temptation to abuse internal
addresses in future, where sternly worded comments have not sufficed.
Instead of having hard-coded addresses and saying "please don't abuse
these", we actually pull the addresses out of the ELF payload into
zoffset.h, and make build.c shove them back into the right places in
the bzImage header.

Rather than including zoffset.h into build.c and thus having to rebuild
the tool for every kernel build, we parse it instead. The parsing code
is small and simple.

This patch doesn't actually move any of the interesting entry points, so
any offending bootloader will still continue to "work" after this patch
is applied. For some version of "work" which includes jumping into the
compressed payload and crashing, if the bzImage it's given is a 32-bit
kernel. No change there then.

[ hpa: some of the issues in the description are addressed or
  retconned by the 2.12 boot protocol.  This patch has been edited to
  only remove fixed addresses that were *not* thus retconned. ]

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1358513837.2397.247.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Matt Fleming <matt.fleming@intel.com>
x86, boot: Explicitly include autoconf.h for hostprogs 2012-10-14T19:41:28+00:00 Matt Fleming matt.fleming@intel.com 2012-10-12T10:19:59+00:00 b6eea87fc6850d3531a64a27d2323a4498cd4e43 The hostprogs need access to the CONFIG_* symbols found in include/generated/autoconf.h. But commit abbf1590de22 ("UAPI: Partition the header include path sets and add uapi/ header directories") replaced $(LINUXINCLUDE) with $(USERINCLUDE) which doesn't contain the necessary include paths. This has the undesirable effect of breaking the EFI boot stub because the #ifdef CONFIG_EFI_STUB code in arch/x86/boot/tools/build.c is never compiled. It should also be noted that because $(USERINCLUDE) isn't exported by the top-level Makefile it's actually empty in arch/x86/boot/Makefile. Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
The hostprogs need access to the CONFIG_* symbols found in
include/generated/autoconf.h.  But commit abbf1590de22 ("UAPI: Partition
the header include path sets and add uapi/ header directories") replaced
$(LINUXINCLUDE) with $(USERINCLUDE) which doesn't contain the necessary
include paths.

This has the undesirable effect of breaking the EFI boot stub because
the #ifdef CONFIG_EFI_STUB code in arch/x86/boot/tools/build.c is
never compiled.

It should also be noted that because $(USERINCLUDE) isn't exported by
the top-level Makefile it's actually empty in arch/x86/boot/Makefile.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
UAPI: Partition the header include path sets and add uapi/ header directories 2012-10-02T17:01:26+00:00 David Howells dhowells@redhat.com 2012-10-02T17:01:26+00:00 abbf1590de22a6d2240a59383477da50d1402f6a Partition the header include path flags into two sets, one for kernelspace builds and one for userspace builds. Add the following directories to build after the ordinary include directories so that #include will pick up the UAPI header directly if the kernel header has been moved there. The userspace set (represented by the USERINCLUDE make variable) contains: -I $(srctree)/arch/$(hdr-arch)/include/uapi -I arch/$(hdr-arch)/include/generated/uapi -I $(srctree)/include/uapi -I include/generated/uapi -include $(srctree)/include/linux/kconfig.h and the kernelspace set (represented by the LINUXINCLUDE make variable) contains: -I $(srctree)/arch/$(hdr-arch)/include -I arch/$(hdr-arch)/include/generated -I $(srctree)/include -I include --- if not building in the source tree plus everything in the USERINCLUDE set. Then use USERINCLUDE in building the x86 boot code. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com> 
Partition the header include path flags into two sets, one for kernelspace
builds and one for userspace builds.

Add the following directories to build after the ordinary include directories
so that #include will pick up the UAPI header directly if the kernel header
has been moved there.

The userspace set (represented by the USERINCLUDE make variable) contains:

	-I $(srctree)/arch/$(hdr-arch)/include/uapi
	-I arch/$(hdr-arch)/include/generated/uapi
	-I $(srctree)/include/uapi
	-I include/generated/uapi
	-include $(srctree)/include/linux/kconfig.h

and the kernelspace set (represented by the LINUXINCLUDE make variable)
contains:

	-I $(srctree)/arch/$(hdr-arch)/include
	-I arch/$(hdr-arch)/include/generated
	-I $(srctree)/include
	-I include		--- if not building in the source tree

plus everything in the USERINCLUDE set.

Then use USERINCLUDE in building the x86 boot code.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
x86, build: Globally set -fno-pic 2012-08-10T23:12:30+00:00 Andrew Boie andrew.p.boie@intel.com 2012-08-10T18:49:06+00:00 484d90eec884d814b005c9736bcf3fd018acba65 GCC built with nonstandard options can enable -fpic by default. We never want this for 32-bit kernels and it will break the build. [ hpa: Notably the Android toolchain apparently does this. ] Change-Id: Iaab7d66e598b1c65ac4a4f0229eca2cd3d0d2898 Signed-off-by: Andrew Boie <andrew.p.boie@intel.com> Link: http://lkml.kernel.org/r/1344624546-29691-1-git-send-email-andrew.p.boie@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
GCC built with nonstandard options can enable -fpic by default.
We never want this for 32-bit kernels and it will break the build.

[ hpa: Notably the Android toolchain apparently does this. ]

Change-Id: Iaab7d66e598b1c65ac4a4f0229eca2cd3d0d2898
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Link: http://lkml.kernel.org/r/1344624546-29691-1-git-send-email-andrew.p.boie@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86, boot: Correct CFLAGS for hostprogs 2012-03-22T19:42:51+00:00 H. Peter Anvin hpa@zytor.com 2012-03-22T18:08:18+00:00 446e1c86d51d0823e003a43a2b85c430efce2733 This is a partial revert of commit: d40f833 "Restrict CFLAGS for hostprogs" The endian-manipulation macros in tools/include need <linux/types.h>, but the hostprogs in arch/x86/boot need several headers from the kernel build tree, which means we have to add the kernel headers to the include path. This picks up <linux/types.h> from the kernel tree, which gives a warning. Since this use of <linux/types.h> is intentional, add -D__EXPORTED_HEADERS__ to the command line to silence the warning. A better way to fix this would be to always install the exported kernel headers into $(objtree)/usr/include as a standard part of the kernel build, but that is a lot more involved. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1330436245-24875-5-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
This is a partial revert of commit:
    d40f833 "Restrict CFLAGS for hostprogs"

The endian-manipulation macros in tools/include need <linux/types.h>,
but the hostprogs in arch/x86/boot need several headers from the
kernel build tree, which means we have to add the kernel headers to
the include path.  This picks up <linux/types.h> from the kernel tree,
which gives a warning.

Since this use of <linux/types.h> is intentional, add
-D__EXPORTED_HEADERS__ to the command line to silence the warning.

A better way to fix this would be to always install the exported
kernel headers into $(objtree)/usr/include as a standard part of the
kernel build, but that is a lot more involved.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-5-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, boot: Restrict CFLAGS for hostprogs 2012-02-28T18:22:59+00:00 Matt Fleming matt.fleming@intel.com 2012-02-28T13:37:23+00:00 d40f833630a1299fd377408dc8d8fac370d621b0 Currently tools/build has access to all the kernel headers in $(srctree). This is unnecessary and could potentially allow tools/build to erroneously include kernel headers when it should only be including userspace-exported headers. Unfortunately, mkcpustr still needs access to some of the asm kernel headers, so explicitly special case that hostprog. Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1330436245-24875-5-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
Currently tools/build has access to all the kernel headers in
$(srctree). This is unnecessary and could potentially allow
tools/build to erroneously include kernel headers when it should only
be including userspace-exported headers.

Unfortunately, mkcpustr still needs access to some of the asm kernel
headers, so explicitly special case that hostprog.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-5-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, build: Do not set the root_dev field in bzImage 2011-05-25T19:46:05+00:00 Michal Marek mmarek@suse.cz 2011-04-12T11:30:24+00:00 079f85e624189292d1c818b47764916bf8cf84a8 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> 
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>
x86, setup: reorganize the early console setup 2010-08-02T22:51:56+00:00 Yinghai Lu yinghai@kernel.org 2010-08-02T09:17:31+00:00 f4ed2877b16e8146427306aea8819adac5c88374 Separate early_serial_console from tty.c This allows for reuse of early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/. -v2: according to hpa, don't include string.c etc -v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c for setup code Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4C568D2B.205@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
Separate early_serial_console from tty.c

This allows for reuse of
early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/.

-v2: according to hpa, don't include string.c etc
-v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c
     for setup code

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C568D2B.205@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
gcov: enable GCOV_PROFILE_ALL for x86_64 2009-06-18T20:03:58+00:00 Peter Oberparleiter oberpar@linux.vnet.ibm.com 2009-06-17T23:28:09+00:00 7bf99fb673f18408be1ebc958321ef4c3f6da9e2 Enable gcov profiling of the entire kernel on x86_64. Required changes include disabling profiling for: * arch/kernel/acpi/realmode and arch/kernel/boot/compressed: not linked to main kernel * arch/vdso, arch/kernel/vsyscall_64 and arch/kernel/hpet: profiling causes segfaults during boot (incompatible context) Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Enable gcov profiling of the entire kernel on x86_64. Required changes
include disabling profiling for:

* arch/kernel/acpi/realmode and arch/kernel/boot/compressed:
  not linked to main kernel
* arch/vdso, arch/kernel/vsyscall_64 and arch/kernel/hpet:
  profiling causes segfaults during boot (incompatible context)

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Li Wei <W.Li@Sun.COM>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-06-10T23:14:41+00:00 Linus Torvalds torvalds@linux-foundation.org 2009-06-10T23:14:41+00:00 bec706838ec2f9c8c2b99e88a1270d7cba159b06 * 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, setup: fix comment in the "glove box" code x86, setup: "glove box" BIOS interrupts in the video code x86, setup: "glove box" BIOS interrupts in the MCA code x86, setup: "glove box" BIOS interrupts in the EDD code x86, setup: "glove box" BIOS interrupts in the APM code x86, setup: "glove box" BIOS interrupts in the core boot code x86, setup: "glove box" BIOS calls -- infrastructure 
* 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, setup: fix comment in the "glove box" code
  x86, setup: "glove box" BIOS interrupts in the video code
  x86, setup: "glove box" BIOS interrupts in the MCA code
  x86, setup: "glove box" BIOS interrupts in the EDD code
  x86, setup: "glove box" BIOS interrupts in the APM code
  x86, setup: "glove box" BIOS interrupts in the core boot code
  x86, setup: "glove box" BIOS calls -- infrastructure