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2006-08-01[PATCH] vDSO hash-style fixRoland McGrath1-0/+14
The latest toolchains can produce a new ELF section in DSOs and dynamically-linked executables. The new section ".gnu.hash" replaces ".hash", and allows for more efficient runtime symbol lookups by the dynamic linker. The new ld option --hash-style={sysv|gnu|both} controls whether to produce the old ".hash", the new ".gnu.hash", or both. In some new systems such as Fedora Core 6, gcc by default passes --hash-style=gnu to the linker, so that a standard invocation of "gcc -shared" results in producing a DSO with only ".gnu.hash". The new ".gnu.hash" sections need to be dealt with the same way as ".hash" sections in all respects; only the dynamic linker cares about their contents. To work with older dynamic linkers (i.e. preexisting releases of glibc), a binary must have the old ".hash" section. The --hash-style=both option produces binaries that a new dynamic linker can use more efficiently, but an old dynamic linker can still handle. The new section runs afoul of the custom linker scripts used to build vDSO images for the kernel. On ia64, the failure mode for this is a boot-time panic because the vDSO's PT_IA_64_UNWIND segment winds up ill-formed. This patch addresses the problem in two ways. First, it mentions ".gnu.hash" in all the linker scripts alongside ".hash". This produces correct vDSO images with --hash-style=sysv (or old tools), with --hash-style=gnu, or with --hash-style=both. Second, it passes the --hash-style=sysv option when building the vDSO images, so that ".gnu.hash" is not actually produced. This is the most conservative choice for compatibility with any old userland. There is some concern that some ancient glibc builds (though not any known old production system) might choke on --hash-style=both binaries. The optimizations provided by the new style of hash section do not really matter for a DSO with a tiny number of symbols, as the vDSO has. If someone wants to use =gnu or =both for their vDSO builds and worry less about that compatibility, just change the option and the linker script changes will make any choice work fine. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Andi Kleen <ak@muc.de> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25kbuild: add option for stripping modules while installing themTheodore Ts'o1-0/+8
Add option for stripping modules while installing them. This function adds support for stripping modules while they are being installed. CONFIG_DEBUG_KERNEL (which will probably become more popular as developers use kdump) causes the size of the installed modules to grow by a factor of 9 or so. Some kernel package systems solve this problem by stripping the debug information from /lib/modules after running "make modules_install", but that may not work for people who are installing directly into /lib/modules --- root partitions that were sized to handle 16 megs worth of modules may not be quite so happy with 145 megs of modules, so the "make modules_install" never succeeds. This patch allows such users to request modules_install to strip the modules as they are installed. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-03-10kbuild: in makefile.txt note that Makefile is preferred name for kbuild filesSam Ravnborg1-3/+3
As noted by Roland Dreier <rdreier@cisco.com> makefiles.txt told one to use the name 'Kbuild' as preferred name for kbuild files. This is not yet true so let makefiles.txt reflect reality. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-02-19kbuild: make cc-version available in kbuild filesSam Ravnborg1-69/+97
Move $(CC) support functions to Kbuild.include so they are available in the kbuild files. In addition the following was done: o as-option documented in Documentation/kbuild/makefiles.txt o Moved documentation to new section to match new scope of functions o added cc-ifversion used to conditionally select a text string dependent on actual $(CC) version o documented cc-ifversion o change so Kbuild.include is read before the kbuild file Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-01-08kbuild: remove GCC_VERSIONSam Ravnborg1-2/+2
This was causing some ordering problems. Remove the up-front evaluation and just revaluate the compiler version each time we need it. (The up-front evaluation was problematic because some architectures modify the value of $(CC)). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-12kbuild: rename prepare to archprepare to fix dependency chainSam Ravnborg1-7/+7
When introducing the generic asm-offsets.h support the dependency chain for the prepare targets was changed. All build scripts expecting include/asm/asm-offsets.h to be made when using the prepare target would broke. With the limited number of prepare targets left in arch Makefiles the trivial solution was to introduce a new arch specific target: archprepare The dependency chain looks like this now: prepare | +--> prepare0 | +--> archprepare | +--> scripts_basic +--> prepare1 | +---> prepare2 | +--> prepare3 So prepare 3 is processed before prepare2 etc. This guaantees that the asm symlink, version.h, scripts_basic are all updated before archprepare is processed. prepare0 which build the asm-offsets.h file will need the actions performed by archprepare. The head target is now named prepare, because users scripts will most likely use that target, but prepare-all has been kept for compatibility. Updated Documentation/kbuild/makefiles.txt. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-29[PATCH] kbuild: describe Kbuild pitfallPaolo 'Blaisorblade' Giarrusso1-0/+6
Whitespace is significant for make, and I just fought against this... so please apply this patch. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-04-17Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+1122
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!