• Lasse Collin's avatar
    x86: support XZ-compressed kernel · 30314804
    Lasse Collin authored
    This integrates the XZ decompression code to the x86 pre-boot code.
    
    mkpiggy.c is updated to reserve about 32 KiB more buffer safety margin for
    kernel decompression.  It is done unconditionally for all decompressors to
    keep the code simpler.
    
    The XZ decompressor needs around 30 KiB of heap, so the heap size is
    increased to 32 KiB on both x86-32 and x86-64.
    
    Documentation/x86/boot.txt is updated to list the XZ magic number.
    
    With the x86 BCJ filter in XZ, XZ-compressed x86 kernel tends to be a few
    percent smaller than the equivalent LZMA-compressed kernel.
    Signed-off-by: default avatarLasse Collin <lasse.collin@tukaani.org>
    Cc: "H. Peter Anvin" <hpa@zytor.com>
    Cc: Alain Knaff <alain@knaff.lu>
    Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
    Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    30314804
boot.txt 34.3 KB