path: root/scripts/link-vmlinux.sh
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2016-11-29kbuild: minor improvement for thin archives buildNicholas Piggin
The root built-in.o archive is currently generated before all object files are built for the final link, due to final build of init/ after version update. In practice it seems like it doesn't matter because the archive symbol table does not change, but it is more logical to create the final archive as the last step. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29kbuild: kallsyms allow 3-pass generation if symbols size has changedNicholas Piggin
kallsyms generation is not foolproof, due to some linkers adding symbols (e.g., branch trampolines) when a binary size changes. Have it attempt a 3rd pass automatically if the kallsyms size changes in the 2nd pass. This allows powerpc64 allyesconfig to build without adding another pass when it's not required. This can be solved other ways by directing the linker not to add labels on branch stubs, or to move kallsyms near the end of the image. The former is undesirable for debugging/tracing, and the latter is a more significant change that requires more testing and review. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-09-09kbuild: allow architectures to use thin archives instead of ld -rStephen Rothwell
ld -r is an incremental link used to create built-in.o files in build subdirectories. It produces relocatable object files containing all its input files, and these are are then pulled together and relocated in the final link. Aside from the bloat, this constrains the final link relocations, which has bitten large powerpc builds with unresolvable relocations in the final link. Alan Modra has recommended the kernel use thin archives for linking. This is an alternative and means that the linker has more information available to it when it links the kernel. This patch enables a config option architectures can select, which causes all built-in.o files to be built as thin archives. built-in.o files in subdirectories do not get symbol table or index attached, which improves speed and size. The final link pass creates a built-in.o archive in the root output directory which includes the symbol table and index. The linker then uses takes this file to link. The --whole-archive linker option is required, because the linker now has visibility to every individual object file, and it will otherwise just completely avoid including those without external references (consider a file with EXPORT_SYMBOL or initcall or hardware exceptions as its only entry points). The traditional built works "by luck" as built-in.o files are large enough that they're going to get external references. However this optimisation is unpredictable for the kernel (due to above external references), ineffective at culling unused, and costly because the .o files have to be searched for references. Superior alternatives for link-time culling should be used instead. Build characteristics for inclink vs thinarc, on a small powerpc64le pseries VM with a modest .config: inclink thinarc sizes vmlinux 15 618 680 15 625 028 sum of all built-in.o 56 091 808 1 054 334 sum excluding root built-in.o 151 430 find -name built-in.o | xargs rm ; time make vmlinux real 22.772s 21.143s user 13.280s 13.430s sys 4.310s 2.750s - Final kernel pulled in only about 6K more, which shows how ineffective the object file culling is. - Build performance looks improved due to less pagecache activity. On IO constrained systems it could be a bigger win. - Build size saving is significant. Side note, the toochain understands archives, so there's some tricks, $ ar t built-in.o # list all files you linked with $ size built-in.o # and their sizes $ objdump -d built-in.o # disassembly (unrelocated) with filenames Implementation by sfr, minor tweaks by npiggin. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-07GCC plugin infrastructureEmese Revfy
This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-07ARM: 8552/1: kallsyms: remove special lower address limit for CONFIG_ARMArd Biesheuvel
Now that we no longer emit .stubs symbols into a section VMA loaded at absolute address 0x1000, we can drop the ARM-specific override that sets a lower limit based on CONFIG_PAGE_OFFSET, below which symbols are filtered from the kallsyms output. Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Chris Brandt <chris.brandt@renesas.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-03-24Merge branch 'kbuild' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - make dtbs_install fix - Error handling fix fixdep and link-vmlinux.sh - __UNIQUE_ID fix for clang - Fix for if_changed_* to suppress the "is up to date." message - The kernel is built with -Werror=incompatible-pointer-types * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild: Add option to turn incompatible pointer check into error kbuild: suppress annoying "... is up to date." message kbuild: fixdep: Check fstat(2) return value scripts/link-vmlinux.sh: force error on kallsyms failure Kbuild: provide a __UNIQUE_ID for clang dtbsinstall: don't move target directory out of the way
2016-03-15kallsyms: add support for relative offsets in kallsyms address tableArd Biesheuvel
Similar to how relative extables are implemented, it is possible to emit the kallsyms table in such a way that it contains offsets relative to some anchor point in the kernel image rather than absolute addresses. On 64-bit architectures, it cuts the size of the kallsyms address table in half, since offsets between kernel symbols can typically be expressed in 32 bits. This saves several hundreds of kilobytes of permanent .rodata on average. In addition, the kallsyms address table is no longer subject to dynamic relocation when CONFIG_RELOCATABLE is in effect, so the relocation work done after decompression now doesn't have to do relocation updates for all these values. This saves up to 24 bytes (i.e., the size of a ELF64 RELA relocation table entry) per value, which easily adds up to a couple of megabytes of uncompressed __init data on ppc64 or arm64. Even if these relocation entries typically compress well, the combined size reduction of 2.8 MB uncompressed for a ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500 KB space saving in the compressed image. Since it is useful for some architectures (like x86) to retain the ability to emit absolute values as well, this patch also adds support for capturing both absolute and relative values when KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu addresses as positive 32-bit values, and addresses relative to the lowest encountered relative symbol as negative values, which are subtracted from the runtime address of this base symbol to produce the actual address. Support for the above is enabled by default for all architectures except IA-64 and Tile-GX, whose symbols are too far apart to capture in this manner. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15x86: kallsyms: disable absolute percpu symbols on !SMPArd Biesheuvel
scripts/kallsyms.c has a special --absolute-percpu command line option which deals with the zero based per cpu offsets that are used when building for SMP on x86_64. This means that the option should only be passed in that case, so add a Kconfig symbol with the correct predicate, and use that instead. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-08scripts/link-vmlinux.sh: force error on kallsyms failureArd Biesheuvel
Since the output of the invocation of scripts/kallsyms is piped directly into the assembler, error messages it emits are visible on stderr, but a non-zero return code is ignored, and the build simply proceeds in that case. However, the resulting kernel is most likely broken, and will crash at boot. So instead, capture the output of kallsyms in a separate .S file, and pass that to the assembler in a separate step. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-01-10um: link with -lpthreadVegard Nossum
Similarly to commit fb1770aa78a43530940d0c2dd161e77bc705bdac, with gcc 5 on Ubuntu and CONFIG_STATIC_LINK=y I was seeing these linker errors: /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new': (.text+0xcd): undefined reference to `pthread_once' /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new': (.text+0x126): undefined reference to `pthread_attr_init' /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new': (.text+0x168): undefined reference to `pthread_attr_setdetachstate' [...] Obviously we also need -lpthread for librt.a. Cc: stable@vger.kernel.org # 4.4 Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-12-08arch: um: fix error when linking vmlinux.Lorenzo Colitti
On gcc Ubuntu 4.8.4-2ubuntu1~14.04, linking vmlinux fails with: arch/um/os-Linux/built-in.o: In function `os_timer_create': /android/kernel/android/arch/um/os-Linux/time.c:51: undefined reference to `timer_create' arch/um/os-Linux/built-in.o: In function `os_timer_set_interval': /android/kernel/android/arch/um/os-Linux/time.c:84: undefined reference to `timer_settime' arch/um/os-Linux/built-in.o: In function `os_timer_remain': /android/kernel/android/arch/um/os-Linux/time.c:109: undefined reference to `timer_gettime' arch/um/os-Linux/built-in.o: In function `os_timer_one_shot': /android/kernel/android/arch/um/os-Linux/time.c:132: undefined reference to `timer_settime' arch/um/os-Linux/built-in.o: In function `os_timer_disable': /android/kernel/android/arch/um/os-Linux/time.c:145: undefined reference to `timer_settime' This is because -lrt appears in the generated link commandline after arch/um/os-Linux/built-in.o. Fix this by removing -lrt from arch/um/Makefile and adding it to the UM-specific section of scripts/link-vmlinux.sh. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Richard Weinberger <richard@nod.at>
2015-05-21scripts: link-vmlinux: Don't pass page offset to kallsyms if XIP KernelMaxime Coquelin
When Kernel is executed in place from ROM, the symbol addresses can be lower than the page offset. Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com> Tested-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-05-07scripts: fix link-vmlinux.sh bash-ismSylvain BERTRAND
While building linux with dash shell: LINK vmlinux trap: SIGHUP: bad trap /src/linux-4.0/Makefile:933: recipe for target 'vmlinux' failed make[1]: *** [vmlinux] Error 1 See the following document for behavior of posix shell trap instruction: http://pubs.opengroup.org/onlinepubs/000095399/utilities/trap.html Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sylvain BERTRAND <sylvain.bertrand@gmail.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-20kbuild: Make scripts executableMichal Marek
The Makefiles call the respective interpreter explicitly, but this makes it easier to use the scripts manually. Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-03-17kallsyms: fix percpu vars on x86-64 with relocation.Rusty Russell
x86-64 has a problem: per-cpu variables are actually represented by their absolute offsets within the per-cpu area, but the symbols are not emitted as absolute. Thus kallsyms naively creates them as offsets from _text, meaning their values change if the kernel is relocated (especially noticeable with CONFIG_RANDOMIZE_BASE): $ egrep ' (gdt_|_(stext|_per_cpu_))' /root/kallsyms.nokaslr 0000000000000000 D __per_cpu_start 0000000000004000 D gdt_page 0000000000014280 D __per_cpu_end ffffffff810001c8 T _stext ffffffff81ee53c0 D __per_cpu_offset $ egrep ' (gdt_|_(stext|_per_cpu_))' /root/kallsyms.kaslr1 000000001f200000 D __per_cpu_start 000000001f204000 D gdt_page 000000001f214280 D __per_cpu_end ffffffffa02001c8 T _stext ffffffffa10e53c0 D __per_cpu_offset Making them absolute symbols is the Right Thing, but requires fixes to the relocs tool. So for the moment, we add a --absolute-percpu option which makes them absolute from a kallsyms perspective: $ egrep ' (gdt_|_(stext|_per_cpu_))' /proc/kallsyms # no KASLR 0000000000000000 A __per_cpu_start 000000000000a000 A gdt_page 0000000000013040 A __per_cpu_end ffffffff802001c8 T _stext ffffffff8099b180 D __per_cpu_offset ffffffff809a3000 D __per_cpu_load $ egrep ' (gdt_|_(stext|_per_cpu_))' /proc/kallsyms # With KASLR 0000000000000000 A __per_cpu_start 000000000000a000 A gdt_page 0000000000013040 A __per_cpu_end ffffffff89c001c8 T _stext ffffffff8a39d180 D __per_cpu_offset ffffffff8a3a5000 D __per_cpu_load Based-on-the-original-screenplay-by: Andy Honig <ahonig@google.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Kees Cook <keescook@chromium.org>
2013-12-10scripts/link-vmlinux.sh: only filter kernel symbols for armMing Lei
Actually CONFIG_PAGE_OFFSET isn't same with PAGE_OFFSET, so it isn't easy to figue out PAGE_OFFSET defined in header file from scripts. Because CONFIG_PAGE_OFFSET may not be defined in some ARCHs( 64bit ARCH), or defined as bogus value in !MMU case, so this patch only applys the filter on ARM when CONFIG_PAGE_OFFSET is defined as the original problem is only on ARM. Cc: <stable@vger.kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Fixes: f6537f2f0eba4eba3354e48dbe3047db6d8b6254 Singed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-11-02scripts/kallsyms: filter symbols not in kernel address spaceMing Lei
This patch uses CONFIG_PAGE_OFFSET to filter symbols which are not in kernel address space because these symbols are generally for generating code purpose and can't be run at kernel mode, so we needn't keep them in /proc/kallsyms. For example, on ARM there are some symbols which may be linked in relocatable code section, then perf can't parse symbols any more from /proc/kallsyms, this patch fixes the problem (introduced b9b32bf70f2fb710b07c94e13afbc729afe221da) Cc: Russell King <linux@arm.linux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Cc: Michal Marek <mmarek@suse.cz> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@vger.kernel.org
2013-03-15CONFIG_SYMBOL_PREFIX: cleanup.Rusty Russell
We have CONFIG_SYMBOL_PREFIX, which three archs define to the string "_". But Al Viro broke this in "consolidate cond_syscall and SYSCALL_ALIAS declarations" (in linux-next), and he's not the first to do so. Using CONFIG_SYMBOL_PREFIX is awkward, since we usually just want to prefix it so something. So various places define helpers which are defined to nothing if CONFIG_SYMBOL_PREFIX isn't set: 1) include/asm-generic/unistd.h defines __SYMBOL_PREFIX. 2) include/asm-generic/vmlinux.lds.h defines VMLINUX_SYMBOL(sym) 3) include/linux/export.h defines MODULE_SYMBOL_PREFIX. 4) include/linux/kernel.h defines SYMBOL_PREFIX (which differs from #7) 5) kernel/modsign_certificate.S defines ASM_SYMBOL(sym) 6) scripts/modpost.c defines MODULE_SYMBOL_PREFIX 7) scripts/Makefile.lib defines SYMBOL_PREFIX on the commandline if CONFIG_SYMBOL_PREFIX is set, so that we have a non-string version for pasting. (arch/h8300/include/asm/linkage.h defines SYMBOL_NAME(), too). Let's solve this properly: 1) No more generic prefix, just CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX. 2) Make linux/export.h usable from asm. 3) Define VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR(). 4) Make everyone use them. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: James Hogan <james.hogan@imgtec.com> Tested-by: James Hogan <james.hogan@imgtec.com> (metag)
2013-02-25kbuild: Fix reading of .config in link-vmlinux.shMichal Marek
The shell '.' command is not required to search the current directory as a fallback and in fact newer versions of bash in sh-mode do not do this. Force reading the file from the current directory if $KCONFIG_CONFIG contains no '/'. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-02-22scripts/link-vmlinux.sh: source variables from KCONFIG_CONFIGMichael Grzeschik
Its possible to superseed the config file with KCONFIG_CONFIG and have completely no .config in the tree. The current script is sourcing .config in every case, so the kernel will never build succesfully. This patch fixes that issue by sourcing KCONFIG_CONFIG instead. Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-09-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lliubbo/blackfin Pull blackfin updates from Bob Liu: "One kbuild and a smp build fix." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lliubbo/blackfin: kbuild: add symbol prefix arg to kallsyms blackfin: smp: adapt to generic smp helpers
2012-09-11kbuild: add symbol prefix arg to kallsymsJames Hogan
Commit 1f2bfbd00e466ff3489b2ca5cc75b1cccd14c123 ("kbuild: link of vmlinux moved to a script") introduced in v3.5-rc1 broke kallsyms on architectures which have symbol prefixes. The --symbol-prefix argument used to be added to the KALLSYMS command line from the architecture Makefile, however this isn't picked up by the new scripts/link-vmlinux.sh. This resulted in symbols like kallsyms_addresses being added which weren't correctly overriding the weak symbols such as _kallsyms_addresses. These could then trigger BUG_ONs in kallsyms code. This is fixed by removing the KALLSYMS addition from the architecture Makefile, and using CONFIG_SYMBOL_PREFIX in the link-vmlinux.sh script to determine whether to add the --symbol-prefix argument. Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Bob Liu <lliubbo@gmail.com>
2012-08-10link-vmlinux.sh: Fix stray "echo" in error messageMichal Marek
Reported-by: Jan Engelhardt <jengelh@inai.de> Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-07-07kbuild: Print errors to stderrMichal Marek
... at least in the top-level Makefile and scripts/link-vmlinux.sh. There are some more instances of the 'echo <error>; exit 1' pattern in some arch Makefiles and kconfig. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-05-28Merge branch 'kbuild' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek. Fixed up nontrivial merge conflict in Makefile as per Stephen Rothwell and linux-next (and trivial arch/sparc/Makefile changes due to removed sparc32 logic). * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: mips: Fix KBUILD_CPPFLAGS definition kbuild: fix ia64 link kbuild: document KBUILD_LDS, KBUILD_VMLINUX_{INIT,MAIN} and LDFLAGS_vmlinux kbuild: link of vmlinux moved to a script kbuild: refactor final link of sparc32 kbuild: drop unused KBUILD_VMLINUX_OBJS from top-level Makefile kbuild: Makefile: remove unnecessary check for m68knommu ARCH
2012-05-10kbuild: fix ia64 linkSam Ravnborg
ia64 build failed like this: CC init/version.o LD init/built-in.o KSYM .tmp_kallsyms1.o ld: .tmp_kallsyms1.o: linking constant-gp files with non-constant-gp files ld: failed to merge target specific data of file .tmp_kallsyms1.o make: *** [vmlinux] Error 1 This was introduced when link of vmlinux was migrated to a script. Add missing option to as to fix this. Reported-by: Tony Luck <tony.luck@gmail.com> Tested-by: Tony Luck <tony.luck@gmail.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Michal Marek <mmarek@suse.cz>
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>