kbuild: Use CRC32 and a 1MiB dictionary for XZ compressed modules

commit fbf5892df21a8ccfcb2fda0fd65bc3169c89ed28 upstream.

Kmod is now (since kmod commit 09c9f8c5df04 ("libkmod: Use kernel
decompression when available")) using the kernel decompressor, when
loading compressed modules.

However, the kernel XZ decompressor is XZ Embedded, which doesn't
handle CRC64 and dictionaries larger than 1MiB.

Use CRC32 and 1MiB dictionary when XZ compressing and installing
kernel modules.

Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1050582
Signed-off-by: Martin Nybo Andersen <tweek@tweek.dk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/scripts/Makefile.modinst b/scripts/Makefile.modinst
index ff9b09e4cfca0c989bad14ca3002c352277a48b6..08cbb25cae98e48b1058aabc3e2422fb3c5eb5d8 100644 (file)
--- a/scripts/Makefile.modinst
+++ b/scripts/Makefile.modinst
@@ -95,7 +95,7 @@ endif
 quiet_cmd_gzip = GZIP    $@
       cmd_gzip = $(KGZIP) -n -f $<
 quiet_cmd_xz = XZ      $@
-      cmd_xz = $(XZ) --lzma2=dict=2MiB -f $<
+      cmd_xz = $(XZ) --check=crc32 --lzma2=dict=1MiB -f $<
 quiet_cmd_zstd = ZSTD    $@
       cmd_zstd = $(ZSTD) -T0 --rm -f -q $<