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2012-10-02UAPI: Partition the header include path sets and add uapi/ header directoriesDavid Howells
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>
2012-05-05kbuild: link of vmlinux moved to a scriptSam Ravnborg
Move the final link of vmlinux to a script to improve readability and maintainability of the code. The Makefile fragments used to link vmlinux has over the years seen far too many changes and the logic had become hard to follow. As the process by nature is serialized there was nothing gained including this in the Makefile. "um" has special link requirments - and the only way to handle this was to hard-code the linking of "um" in the script. This was better than trying to modularize it only for the benefit of "um" anyway. The shell script has been improved after input from: Arnaud Lacombe <lacombar@gmail.com> Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Arnaud Lacombe <lacombar@gmail.com> Cc: Nick Bowler <nbowler@elliptictech.com> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-03-25um: Switch to large mcmodel on x86_64Richard Weinberger
x86_64 UML is unable to load modules if more than 504MiB of memory are used. This happens because on x86_64 the UML process has a quite high start address (typically around 0x6000000). If UML's memory is larger than 504MiB VMALLOC_START happens to be after 0x8000000. This is no problem unless one loads a module which was built with R_X86_64_32S relocations. Symbols with a location > 0x8000000 cannot be used with R_X86_64_32S To deal with this x86_64 UML has to be compiled with -mcmodel=large such that no R_X86_64_32S relocations are used. Signed-off-by: Richard Weinberger <richard@nod.at> Reported-by: 전하늘 <allskyee@gmail.com>
2012-03-25um: most of the SUBARCH uses can be killedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [richard@nod.at: Re-export SUBARCH in arch/um/Makefile] Signed-off-by: Richard Weinberger <richard@nod.at>
2011-12-09um: Use $(srctree) not $(KBUILD_SRC)H. Peter Anvin
$(KBUILD_SRC) is not defined without O=, use $(srctree). Reported-and-tested-by: Richard Weinberger <richard@nod.at> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-12-05um: Generate headers before generating user-offsets.sH. Peter Anvin
In case we need generated header files for the values in user-offsets.h, make sure we build generated header files before user-offsets.s is built. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-05um: Run host archheaders, allow use of host generated headersH. Peter Anvin
Run the "archheaders" target for the host architecture, for architectures (like x86, now) that want to generate some of the necessary header files. Add $(HOST_DIR)/include/generated to the include path so we then pick them up. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-11-02um: take arch/um/sys-x86 to arch/x86/umAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge Makefile-{i386,x86_64}Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge arch/um/sys-{i386,x86_64}Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge arch/um/sys-{i386,x86_64}/sharedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: merge arch/um/sys-{i386,x86_64}/asmAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: get rid of kern_constants.hAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: take user_constants.h to include/generatedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-11-02um: switch to -idirafter, get saner kern_constants.h out of thatAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
2011-09-14um: fix strrchr() problemsAl Viro
richard@nod.at: Fixes: /usr/lib/gcc/x86_64-linux-gnu/4.4.5/../../../../lib/libc.a(strrchr.o): In function `rindex': (.text+0x0): multiple definition of `strrchr' If both STATIC_LINK and UML_NET_VDE are set to "y" libc's strrchr may clash with the kernel implementation. This workaround comes originally from Jeff Dike: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=494995#35 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-12kbuild: move asm-offsets.h to include/generatedSam Ravnborg
The simplest method was to add an extra asm-offsets.h file in arch/$ARCH/include/asm that references the generated file. We can now migrate the architectures one-by-one to reference the generated file direct - and when done we can delete the temporary arch/$ARCH/include/asm/asm-offsets.h file. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Michal Marek <mmarek@suse.cz>
2009-09-20arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0Sam Ravnborg
Albin Tonnerre <albin.tonnerre@free-electrons.com> reported: Bash 4 filters out variables which contain a dot in them. This happends to be the case of CPPFLAGS_vmlinux.lds. This is rather unfortunate, as it now causes build failures when using SHELL=/bin/bash to compile, or when bash happens to be used by make (eg when it's /bin/sh) Remove the common definition of CPPFLAGS_vmlinux.lds by pushing relevant stuff to either Makefile.build or the arch specific kernel/Makefile where we build the linker script. This is also nice cleanup as we move the information out where it is used. Notes for the different architectures touched: arm - we use an already exported symbol cris - we use a config symbol aleady available [Not build tested] mips - the jiffies complexity has moved to vmlinux.lds.S where we need it. Added a few variables to CPPFLAGS - they are only used by the linker script. [Not build tested] powerpc - removed assignment that is not needed [not build tested] sparc - simplified it using $(BITS) um - introduced a few new exported variables to deal with this xtensa - added options to CPP invocation [not build tested] Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-01-05get rid of the last symlink in uml buildAl Viro
We need to make asm-offsets.h contents visible for objects built with userland headers. Instead of creating a symlink, just have the file with equivalent include (relative to location of header) created once. That kills the last symlink used in arch/um builds. Additionally, both generated headers can become dependencies of archprepare now, killing the misuse of prepare. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-22x86, um: get rid of uml-config.hAl Viro
Take a few symbols we need into kern_constants.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of arch/um/Kconfig.archAl Viro
Teach scripts/kconfig/Makefile and top-level Makefile that arch/*/Makefile is allowed to say Kconfig := <whatever I want instead of arch/blah/Kconfig>. Rewrite arch/um/Kconfig and arch/um/Kconfig.<subarch> so that the latter would be top-level one (and include the pieces of the former). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of arch/um/os symlinkAl Viro
we can get DEV_NULL defined for arch/um/drivers/null.c in less convoluted ways, TYVM... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of header symlinksAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: merge Kconfig.i386 and Kconfig.x86_64Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of sysdep symlinkAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: take vm-flags.h to sysdepAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of uml asm/archAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: get rid of system.h -> system.h includeAl Viro
Long-term we want to split system.h and include barriers part from underlying target; for now copy that part to sysdep. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: untangle uml ldt.hAl Viro
* turn asm/ldt.h into ldt.h; update the (very few) users * take host_ldt.h into sysdep, kill symlink mess * includes of asm/arch/ldt.h turn into asm/ldt.h now Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: sanitize uml sigcontext.h usesAl Viro
a) the only difference between sigcontext and sysdep/sigcontext is that the former contains externs for two long-dead functions. Removed, switched the only user to sysdep/sigcontext b) asm/sigcontext.h is removable - that of underlying architecture would get used. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: now we can get rid of trivial uml headersAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: ... and asm-x86 moveAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: initial part of asm-um moveAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22x86, um: take arch/um/include/* out of the wayAl Viro
We can't just plop asm/* into it - userland helpers are built with it in search path and seeing asm/* show up there suddenly would be a bad idea. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-07-07[UML] fix gcc ICEs and unresolved externsJeff Dike
There are various constraints on the use of unit-at-a-time: - i386 uses no-unit-at-a-time for pre-4.0 (not 4.3) - x86_64 uses unit-at-a-time always Uli reported a crash on x86_64 with gcc 4.1.2 with unit-at-a-time, resulting in commit c0a18111e571138747a98af18b3a2124df56a0d1 Ingo reported a gcc internal error with gcc 4.3 with no-unit-at-a-timem, resulting in 22eecde2f9034764a3fd095eecfa3adfb8ec9a98 Benny Halevy is seeing extern inlines not resolved with gcc 4.3 with no-unit-at-a-time This patch reintroduces unit-at-a-time for gcc >= 4.0, bringing back the possibility of Uli's crash. If that happens, we'll debug it. I started seeing both the internal compiler errors and unresolved inlines on Fedora 9. This patch fixes both problems, without so far reintroducing the crash reported by Uli. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Benny Halevy <bhalevy@panasas.com> Cc: Adrian Bunk <bunk@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-06Revert "uml: fix gcc problem"Linus Torvalds
This reverts commit 22eecde2f9034764a3fd095eecfa3adfb8ec9a98. Uli reports that it breaks UML on x86-64 with the Fedora 8 gcc (gcc 4.1.2), causing a crash on startup. See http://marc.info/?l=linux-kernel&m=121011722806093&w=2 for a trace. Reported-by: Ulrich Drepper <drepper@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-04uml: fix gcc problemIngo Molnar
this is what caused gcc 4.3 to throw an internal error when OPTIMIZE_INLINING was enabled ... Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-08uml: runtime host VMSPLIT detectionJeff Dike
Calculate TASK_SIZE at run-time by figuring out the host's VMSPLIT - this is needed on i386 if UML is to run on hosts with varying VMSPLITs without recompilation. TASK_SIZE is now defined in terms of a variable, task_size. This gets rid of an include of pgtable.h from processor.h, which can cause include loops. On i386, task_size is calculated early in boot by probing the address space in a binary search to figure out where the boundary between usable and non-usable memory is. This tries to make sure that a page that is considered to be in userspace is, or can be made, read-write. I'm concerned about a system-global VDSO page in kernel memory being hit and considered to be a userspace page. On x86_64, task_size is just the old value of CONFIG_TOP_ADDR. A bunch of config variable are gone now. CONFIG_TOP_ADDR is directly replaced by TASK_SIZE. NEST_LEVEL is gone since the relocation of the stubs makes it irrelevant. All the HOST_VMSPLIT stuff is gone. All references to these in arch/um/Makefile are also gone. I noticed and fixed a missing extern in os.h when adding os_get_task_size. Note: This has been revised to fix the 32-bit UML on 64-bit host bug that Miklos ran into. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05uml: remove TOPDIRWANG Cong
TOPDIR is obsolete, use srctree instead. This patch removes TOPDIR from all UML Makefiles. Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05uml: fx command-line CFLAGS and LDFLAGS supportJeff Dike
UML still needed some work in order to allow CFLAGS to be passed in from the command line. USER_CFLAGS is produced from KBUILD_CFLAGS in part by removing all the -I switches. This is so that kernel headers don't accidentally get pulled into libc files. However, a common use of command-line CFLAGS would be to add -I switches to the build. This patch specifically adds any command-line -I flags back to USER_CFLAGS. I also corrected the spelling of LFLAGS to LDFLAGS. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05uml: allow LFLAGS on command lineJeff Dike
Allow LFLAGS to be given to make and have the expected effect. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29UML: build fixWANG Cong
include/asm-um/arch points to the non-existed include/asm-i386 directory. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@karaya.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14uml: fix symlink loopsJeff Dike
symlinks to directories in the non-O= case were lacking -n, which meant that, when the link already existed, a new link pointing at itself was created in the target directory. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-05uml: correctly strip kernel defines from userspace CFLAGSJeff Dike
KERNEL_DEFINES needs whitespace trimmed, otherwise the whitespace crunching done by make fools the patsubst which is used to remove KERNEL_DEFINES from USER_CFLAGS. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuildLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild: (40 commits) kbuild: introduce ccflags-y, asflags-y and ldflags-y kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP kbuild: enable use of AFLAGS and CFLAGS on commandline kbuild: enable 'make AFLAGS=...' to add additional options to AS kbuild: fix AFLAGS use in h8300 and m68knommu kbuild: check for wrong use of CFLAGS kbuild: enable 'make CFLAGS=...' to add additional options to CC kbuild: fix up CFLAGS usage kbuild: make modpost detect unterminated device id lists kbuild: call export_report from the Makefile kbuild: move Kai Germaschewski to CREDITS kconfig/menuconfig: distinguish between selected-by-another options and comments kconfig: tristate choices with mixed tristate and boolean values include/linux/Kbuild: remove duplicate entries kbuild: kill backward compatibility checks kbuild: kill EXTRA_ARFLAGS kbuild: fix documentation in makefiles.txt kbuild: call make once for all targets when O=.. is used kbuild: pass -g to assembler under CONFIG_DEBUG_INFO kbuild: update _shipped files for kconfig syntax cleanup ... Fix up conflicts in arch/um/sys-{x86_64,i386}/Makefile manually.
2007-10-16uml: style fixes pass 1Jeff Dike
Formatting changes in the files which have been changed in the tt-removal patchset so far. These include: copyright updates header file trimming style fixes adding severity to printks indenting Kconfig help according to the predominant kernel style These changes should be entirely non-functional. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: throw out CONFIG_MODE_TTJeff Dike
This patchset throws out tt mode, which has been non-functional for a while. This is done in phases, interspersed with code cleanups on the affected files. The removal is done as follows: remove all code, config options, and files which depend on CONFIG_MODE_TT get rid of the CHOOSE_MODE macro, which decided whether to call tt-mode or skas-mode code, and replace invocations with their skas portions replace all now-trivial procedures with their skas equivalents There are now a bunch of now-redundant pieces of data structures, including mode-specific pieces of the thread structure, pt_regs, and mm_context. These are all replaced with their skas-specific contents. As part of the ongoing style compliance project, I made a style pass over all files that were changed. There are three such patches, one for each phase, covering the files affected by that phase but no later ones. I noticed that we weren't freeing the LDT state associated with a process when it exited, so that's fixed in one of the later patches. The last patch is a tidying patch which I've had for a while, but which caused inexplicable crashes under tt mode. Since that is no longer a problem, this can now go in. This patch: Start getting rid of tt mode support. This patch throws out CONFIG_MODE_TT and all config options, code, and files which depend on it. CONFIG_MODE_SKAS is gone and everything that depends on it is included unconditionally. The few changed lines are in re-written Kconfig help, lines which needed something skas-related removed from them, and a few more which weren't strictly deletions. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: fix an IPV6 libc vs kernel symbol clashJeff Dike
On some systems, with IPV6 configured, there is a clash between the kernel's in6addr_any and the one in libc. This is handled in the usual (gross) way of defining the kernel symbol out of the way on the gcc command line. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-15kbuild: enable 'make AFLAGS=...' to add additional options to ASSam Ravnborg
The variable AFLAGS is a wellknown variable and the usage by kbuild may result in unexpected behaviour. On top of that several people over time has asked for a way to pass in additional flags to gcc. This patch replace use of AFLAGS with KBUILD_AFLAGS all over the tree. Patch was tested on following architectures: alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390 Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-14kbuild: enable 'make CFLAGS=...' to add additional options to CCSam Ravnborg
The variable CFLAGS is a wellknown variable and the usage by kbuild may result in unexpected behaviour. On top of that several people over time has asked for a way to pass in additional flags to gcc. This patch replace use of CFLAGS with KBUILD_CFLAGS all over the tree and enabling one to use: make CFLAGS=... to specify additional gcc commandline options. One usecase is when trying to find gcc bugs but other use cases has been requested too. Patch was tested on following architectures: alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k Test was simple to do a defconfig build, apply the patch and check that nothing got rebuild. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>