Spectrum Posted May 30, 2012 Share Posted May 30, 2012 Does anyone know how to compress the bzroot with lzma/xz? I've tried using the same syntax as gzip but it's not working decompression with xzcat /path/to/bzroot | cpio -i -d -H newc --no-absolute-filenames works fine but compression using the assumed find . | cpio -o -H newc | xz > /path/to/newbzroot or find . | cpio -o -H newc | xz --stdout - > /path/to/newbzroot creates a new archive but chokes on reboot when trying to extract the initramfs. The boot chokes with: VFS: Cannot open root device"(null)" or unknown-block(8,2) Please append a correct "root=" boot option" here are the available partitions: compressing the same data using gzip works fine though. Makes me think I'm doing something goofy with the compression Using 5.0rc3 and I've attached a screenshot of the kernel puking all over the place. Quote Link to comment
BRiT Posted May 30, 2012 Share Posted May 30, 2012 Did you enable the proper compression support in the linux kernel config? Try using "lzma" located in /usr/bin. It's the same as invoking 'xz' with the lzma option: lzma or xz --format=lzma Quote Link to comment
Spectrum Posted May 30, 2012 Author Share Posted May 30, 2012 ANNNNND epic faceapalm! I was compressing to xz not to lzma. Sometimes it pays to step back and take a break and have fresh eyes take a peek. Appreciate it brit! Quote Link to comment
rmilanov Posted June 11, 2012 Share Posted June 11, 2012 To further this a bit, I saw with the compression change done in 5RC that we now need to use the following to extract bzroot: xzcat /path/to/bzroot | cpio -m -i -d -H newc --no-absolute-filenames Do we need to use a new command to compress? What should we use with the new releases? I seem to be having issues with this as the original RC4 file is about 32Mb and when I compress it jumps to 40Mb. Thanks! Quote Link to comment
BRiT Posted June 11, 2012 Share Posted June 11, 2012 rmilanov, read the thread you posted in. It has the answers. The new command is "xz --format=lzma" or "lzma". Quote Link to comment
rmilanov Posted June 12, 2012 Share Posted June 12, 2012 Ok... if that's correct then I will continue using it. I was just concerned because when I used those my bzroot came out 8Mb larger when I barely added anything to the image. R Quote Link to comment
BRiT Posted June 12, 2012 Share Posted June 12, 2012 Odd. Not sure why it would be that much larger. find . | cpio -o -H newc | xz --format=lzma > /path/to/newbzroot Quote Link to comment
Spectrum Posted June 14, 2012 Author Share Posted June 14, 2012 It could have to do with the default compression level. Not sure what Limetech uses when he compresses the kernel. Any compression with lzma will end up better than .gz though Quote Link to comment
piotrasd Posted June 15, 2012 Share Posted June 15, 2012 try find . | cpio -o -H newc | xz --check=crc32 --x86 --lzma2=preset=9e > /boot/new_bzroot Quote Link to comment
greenythebeast Posted December 26, 2012 Share Posted December 26, 2012 try find . | cpio -o -H newc | xz --check=crc32 --x86 --lzma2=preset=9e > /boot/new_bzroot I tried this and my bzroot went from 33MB to 65MB I changed a few lines of text in two files. How could it go up so much!?!? Quote Link to comment
CHBMB Posted January 11, 2016 Share Posted January 11, 2016 You know this is over three years old right? Quote Link to comment
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