Re: LZMA inclusion

[Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>]

On Wed, Dec 03, 2008 at 09:20:09PM +0100, Sam Ravnborg wrote:
>On Wed, Dec 03, 2008 at 08:58:52PM +0100, Bernhard Reutner-Fischer wrote:
>> On Wed, Dec 03, 2008 at 11:36:45AM -0800, Tim Bird wrote:
>> >Gregers Petersen wrote:
>> >> There was a small talk a few days ago involving a few of the OpenWrt
>> >> developers and David Woodhouse. One of the topics discussed, was a
>> >> question about the potential of including LZMA in the kernel.
>> >> Such an inclusion would be quite benefitial in terms of embedded
>> >> systems, but the major hurdle seems to be the code quality of LZMA itself.
>> >> This leads to the question I would like to raise; are there ongoing
>> >> plans (or considerations) to rewrite and merge LZMA, and has anyone
>> >> started working on it in practical terms?
>> >
>> >Did anyone answer this?  CELF is currently considering funding
>> >a project to do this (add LZMA support to the kernel), and
>> >it would be good to get a feel for the current status...
>> > -- Tim
>> 
>> AFAIK xz will be/is incompatible with this older LZMA, perhaps
>> larhzu wants to chime in on that.
>> 
>> PS: A previous incarnation of that patch didn't work conventiently
>> for me, i had to do some small adjustments to the way it was put
>> into the kernel configury, like
>> http://repo.or.cz/w/buildroot.git?a=blob_plain;f=toolchain/kernel-headers/lzma/linux-2.6.22.1-002-lzma-vmlinuz.01.patch;hb=HEAD
>> http://repo.or.cz/w/buildroot.git?a=blob_plain;f=toolchain/kernel-headers/lzma/linux-2.6.22.1-003-lzma-vmlinuz.patch;hb=HEAD
>
>If these are required with latest kernel could I then ask you to
>properly submit them to: linux-kbuild@vger.kernel.org

AFAIK neither lzma nor xz support was accepted yet and i did not look
if those patchlets are still required for the currently proposed
xz or lzma support.
>
>No need to have good patches sitting at random places.

Of course not, agree. I certainly don't fancy accumulating random
patches for my own personal use, at any rate.

PS: Not sure if you, Sam, are the right person who cares for it, but
i think that the help-text and actual accepted arguments of
scripts/kconfig/lxdialog/check-lxdialog.sh are out of sync.


PPS: I did not verify if this is still the case, but I have this
comment as a reminder for a small issue with "archprepare" versus
headers_install, fwiw. It would be very handy if i could fuse those
two into a simple "make ... archprepare headers_install":
        # some arches need archprepare
        # FIXME: WTH! archprepare does not honour INSTALL_HDR_PATH
        -(cd $(LINUX_HEADERS_UNPACK_DIR); \
         $(MAKE) ARCH=$(KERNEL_ARCH) \
                HOSTCC="$(HOSTCC)" HOSTCFLAGS="$(HOSTCFLAGS)" \
                HOSTCXX="$(HOSTCXX)" \
                KCONFIG_CONFIG="$(LINUX_HEADERS_DIR)/.config" \
                INSTALL_HDR_PATH=$(LINUX_HEADERS_DIR) \
                archprepare \
        )
        (cd $(LINUX_HEADERS_UNPACK_DIR); \
         $(MAKE) ARCH=$(KERNEL_ARCH) \
                HOSTCC="$(HOSTCC)" HOSTCFLAGS="$(HOSTCFLAGS)" \
                HOSTCXX="$(HOSTCXX)" \
                INSTALL_HDR_PATH=$(LINUX_HEADERS_DIR) \
                headers_install \
        )