These 2 patches fix some issues with the current LZO decompressor code.
The first one (re-)enables the use of LZO-compressed external initramfs, which
has been broken for some time. The second one enables the use of in-kernel
initramfs compressed using LZO.
If that's possible, I'd like to get at least patch 1/2 in 2.6.34, since it
is an actual bug fix.
Albin Tonnerre (2):
lib: fix initramfs usage for the LZO decompressor
Add support for in-kernel initramfs compressed with LZO
lib/decompress_unlzo.c | 22 +++++++++++++++-------
scripts/gen_initramfs_list.sh | 1 +
usr/Makefile | 5 ++++-
usr/initramfs_data.lzo.S | 29 +++++++++++++++++++++++++++++
4 files changed, 49 insertions(+), 8 deletions(-)
create mode 100644 usr/initramfs_data.lzo.S
This patch fixes 2 issues with the LZO decompressor:
- It doesn't handle the case where a block isn't compressed at all. In
this case, calling lzo1x_decompress_safe will fail, so we need to
just use memcpy() instead (the upstream LZO code does something
similar)
- Since commit 54291362d2a5738e1b0495df2abcb9e6b0563a3f, the
decompressor return code is checked in the init/initramfs.c
The LZO decompressor didn't return the expected value, causing the
initramfs code to falsely believe a decompression error occured
Signed-off-by: Albin Tonnerre <[email protected]>
Tested-By: bert schulze <[email protected]>
--
lib/decompress_unlzo.c | 22 +++++++++++++++-------
1 files changed, 15 insertions(+), 7 deletions(-)
diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c
index db521f4..bcb3a4b 100644
--- a/lib/decompress_unlzo.c
+++ b/lib/decompress_unlzo.c
@@ -97,7 +97,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
u32 src_len, dst_len;
size_t tmp;
u8 *in_buf, *in_buf_save, *out_buf;
- int obytes_processed = 0;
+ int ret = -1;
set_error_fn(error_fn);
@@ -174,15 +174,22 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
/* decompress */
tmp = dst_len;
- r = lzo1x_decompress_safe((u8 *) in_buf, src_len,
+
+ /* When the input data is not compressed at all,
+ * lzo1x_decompress_safe will fail, so call memcpy()
+ * instead */
+ if (unlikely(dst_len == src_len))
+ memcpy(out_buf, in_buf, src_len);
+ else {
+ r = lzo1x_decompress_safe((u8 *) in_buf, src_len,
out_buf, &tmp);
- if (r != LZO_E_OK || dst_len != tmp) {
- error("Compressed data violation");
- goto exit_2;
+ if (r != LZO_E_OK || dst_len != tmp) {
+ error("Compressed data violation");
+ goto exit_2;
+ }
}
- obytes_processed += dst_len;
if (flush)
flush(out_buf, dst_len);
if (output)
@@ -196,6 +203,7 @@ STATIC inline int INIT unlzo(u8 *input, int in_len,
in_buf += src_len;
}
+ ret = 0;
exit_2:
if (!input)
free(in_buf);
@@ -203,7 +211,7 @@ exit_1:
if (!output)
free(out_buf);
exit:
- return obytes_processed;
+ return ret;
}
#define decompress unlzo
--
1.7.0.4
This patch adds the necessary parts to be enable the use of
LZO-compressed initramfs build into the kernel.
Signed-off-by: Albin Tonnerre <[email protected]>
---
scripts/gen_initramfs_list.sh | 1 +
usr/Makefile | 5 ++++-
usr/initramfs_data.lzo.S | 29 +++++++++++++++++++++++++++++
3 files changed, 34 insertions(+), 1 deletions(-)
create mode 100644 usr/initramfs_data.lzo.S
diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh
index 76af5f9..a932ae5 100644
--- a/scripts/gen_initramfs_list.sh
+++ b/scripts/gen_initramfs_list.sh
@@ -242,6 +242,7 @@ case "$arg" in
echo "$output_file" | grep -q "\.gz$" && compr="gzip -9 -f"
echo "$output_file" | grep -q "\.bz2$" && compr="bzip2 -9 -f"
echo "$output_file" | grep -q "\.lzma$" && compr="lzma -9 -f"
+ echo "$output_file" | grep -q "\.lzo$" && compr="lzop -9 -f"
echo "$output_file" | grep -q "\.cpio$" && compr="cat"
shift
;;
diff --git a/usr/Makefile b/usr/Makefile
index 1e6a9e4..6b4b6da 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -15,6 +15,9 @@ suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) = .bz2
# Lzma
suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZMA) = .lzma
+# Lzo
+suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZO) = .lzo
+
# Generate builtin.o based on initramfs_data.o
obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data$(suffix_y).o
@@ -45,7 +48,7 @@ endif
quiet_cmd_initfs = GEN $@
cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
-targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio
+targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio.lzo initramfs_data.cpio
# do not try to update files included in initramfs
$(deps_initramfs): ;
diff --git a/usr/initramfs_data.lzo.S b/usr/initramfs_data.lzo.S
new file mode 100644
index 0000000..5921190
--- /dev/null
+++ b/usr/initramfs_data.lzo.S
@@ -0,0 +1,29 @@
+/*
+ initramfs_data includes the compressed binary that is the
+ filesystem used for early user space.
+ Note: Older versions of "as" (prior to binutils 2.11.90.0.23
+ released on 2001-07-14) dit not support .incbin.
+ If you are forced to use older binutils than that then the
+ following trick can be applied to create the resulting binary:
+
+
+ ld -m elf_i386 --format binary --oformat elf32-i386 -r \
+ -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
+ ld -m elf_i386 -r -o built-in.o initramfs_data.o
+
+ initramfs_data.scr looks like this:
+SECTIONS
+{
+ .init.ramfs : { *(.data) }
+}
+
+ The above example is for i386 - the parameters vary from architectures.
+ Eventually look up LDFLAGS_BLOB in an older version of the
+ arch/$(ARCH)/Makefile to see the flags used before .incbin was introduced.
+
+ Using .incbin has the advantage over ld that the correct flags are set
+ in the ELF header, as required by certain architectures.
+*/
+
+.section .init.ramfs,"a"
+.incbin "usr/initramfs_data.cpio.lzo"
--
1.7.0.4