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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 16:03:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 16:03:23 -0700 |
| commit | c0dfadfed87489fa6126ece161a14c2d15dbdc79 (patch) | |
| tree | 2b1ac3fb464e4d18b57e3d4735cd6b60454cc972 /arch/x86/boot/header.S | |
| parent | ba77c568f3160657a5f7905289c07d18c2dfde78 (diff) | |
| parent | 1ac1efa5f6950f8f126f2c1921bb699ce009ec7d (diff) | |
Merge tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
"The main change in this cycle was to add support for ZSTD-compressed
kernel and initrd images.
ZSTD has a very fast decompressor, yet it compresses better than gzip"
* tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: dontdiff: Add zstd compressed files
.gitignore: Add ZSTD-compressed files
x86: Add support for ZSTD compressed kernel
x86: Bump ZO_z_extra_bytes margin for zstd
usr: Add support for zstd compressed initramfs
init: Add support for zstd compressed kernel
lib: Add zstd support to decompress
lib: Prepare zstd for preboot environment, improve performance
Diffstat (limited to 'arch/x86/boot/header.S')
| -rw-r--r-- | arch/x86/boot/header.S | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 735ad7f21ab0..6dbd7e9f74c9 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -539,8 +539,14 @@ pref_address: .quad LOAD_PHYSICAL_ADDR # preferred load addr # the size-dependent part now grows so fast. # # extra_bytes = (uncompressed_size >> 8) + 65536 +# +# ZSTD compressed data grows by at most 3 bytes per 128K, and only has a 22 +# byte fixed overhead but has a maximum block size of 128K, so it needs a +# larger margin. +# +# extra_bytes = (uncompressed_size >> 8) + 131072 -#define ZO_z_extra_bytes ((ZO_z_output_len >> 8) + 65536) +#define ZO_z_extra_bytes ((ZO_z_output_len >> 8) + 131072) #if ZO_z_output_len > ZO_z_input_len # define ZO_z_extract_offset (ZO_z_output_len + ZO_z_extra_bytes - \ ZO_z_input_len) |