On 2020-11-28 13:32:09 +0100 (+0100), Dmitry Tantsur wrote: > Is it wildly supported for initramfs compression? I can, of > course, try, but maybe you know. [...] It looks like you need your kernel built with with: CONFIG_HAVE_KERNEL_XZ=y CONFIG_KERNEL_XZ=y CONFIG_RD_XZ=y CONFIG_XZ_DEC=y CONFIG_XZ_DEC_X86=y (or relevant CPU architecture) CONFIG_DECOMPRESS_XZ=y The standard Linux 5.9 kernel on my Debian systems has the above enabled by default, not sure about other distros or older kernels though CONFIG_KERNEL_XZ has been included as far back as Linux 2.38: https://cateee.net/lkddb/web-lkddb/KERNEL_XZ.html Apparently you may need to pass --check=crc32 and (possibly --lzma2=dict=512KiB as well) to xz when compressing your initrd, to accommodate the kernel's decompressor implementation: https://github.com/linuxboot/book/blob/master/coreboot.u-root.systemboot/README.md#building-u-root https://www.linuxquestions.org/questions/slackware-installation-40/booting-with-xz-compressed-initrd-4175599273/ -- Jeremy Stanley -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 833 bytes Desc: not available URL: <http://lists.openstack.org/pipermail/openstack-discuss/attachments/20201128/12981075/attachment.sig>