Bug#831003: support gzip'd kernel image

[Alper Nebi Yasak]

On Thu, 23 May 2019 10:36:15 -0700 Vagrant Cascadian wrote:

Untested and refreshed patch against current git attached.


I wanted to extend this, but I ended up almost completely rewriting it:
https://salsa.debian.org/installer-team/flash-kernel/merge_requests/15/

Instead of only using a compressed kernel as-is, my implementation can 
also decompress/recompress into a preferred format, with many more 
compression types.



Regardless of my MR,


+compress_type() {
+local file="$1"
+magic="$(od -x -N2 $file | head -1 | cut -d' ' -f2)"


If compress_type is called without an argument, od reads from stdin 
which might cause flash-kernel to 'hang' unexpectedly. Quoting "$file" 
instead exits in error.

Bug#831003: support gzip'd kernel image

[Vagrant Cascadian]

On 2016-07-13, dann frazier wrote:
> flash-kernel currently always sets the compression type to "none" when
> generating uImages. However, if the source vmlinuz file is gzip'd - as
> is the case if you build the "Image.gz" kernel target - this will
> prevent U-Boot from being able to boot it[1]. If the uImage is
> generated with a compression type of "gzip", then it boots fine.
>
> The attached patch checks the source image type and sets the
> compression setting appropriately.
>
> [1] At least, this is true on APM Mustang systems

Sorry for the long delay...

Untested and refreshed patch against current git attached.

live well,
  vagrant

From 846e0fec533875605d58a93aa0680fcc31c06c62 Mon Sep 17 00:00:00 2001
From: dann frazier 
Date: Thu, 23 May 2019 10:26:06 -0700
Subject: [PATCH] support gzip'd kernel image (Closes: #831003).

(Refreshed: Vagrant Cascadian flash-kernel 3.99~)
---
 functions  | 18 +-
 test_functions | 25 +
 2 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/functions b/functions
index 1533192..44bc822 100644
--- a/functions
+++ b/functions
@@ -432,15 +432,31 @@ get_kernel_cmdline_defaults() {
 	echo "$LINUX_KERNEL_CMDLINE_DEFAULTS"
 }
 
+compress_type() {
+local file="$1"
+magic="$(od -x -N2 $file | head -1 | cut -d' ' -f2)"
+case $magic in
+8b1f)
+echo "gzip"
+;;
+*)
+echo "none"
+;;
+esac
+}
+
 mkimage_kernel() {
 	local kaddr="$1"
 	local epoint="$2"
 	local kdesc="$3"
 	local kdata="$4"
 	local uimage="$5"
+	local comp
+
+	comp="$(compress_type $kdata)"
 
 	printf "Generating kernel u-boot image... " >&2
-	mkimage -A "$mkarch" -O linux -T kernel -C none -a "$kaddr" -e "$epoint" \
+	mkimage -A "$mkarch" -O linux -T kernel -C "$comp" -a "$kaddr" -e "$epoint" \
 		-n "$kdesc" -d "$kdata" "$uimage" >&2 1>/dev/null
 	echo "done." >&2
 }
diff --git a/test_functions b/test_functions
index eeea52f..74f7880 100755
--- a/test_functions
+++ b/test_functions
@@ -561,7 +561,9 @@ test_set_machine_id() {
 }
 add_test test_set_machine_id
 
-test_mkimage_kernel() {
+_test_mkimage_kernel() {
+local kdata="$1"
+local expected="$2"
 (
 mkimage() {
 saved_args="$@"
@@ -569,16 +571,31 @@ test_mkimage_kernel() {
 . "$functions"
 saved_args=""
 mkarch="arm"
-mkimage_kernel "0xdeadbeef" "0xbaddcafe" "desc" "input" "output" 2>/dev/null
-expected="-A arm -O linux -T kernel -C none -a 0xdeadbeef -e 0xbaddcafe -n desc -d input output"
+mkimage_kernel "0xdeadbeef" "0xbaddcafe" "desc" "$kdata" "output" 2>/dev/null
 if [ "$expected" != "$saved_args" ]; then
 echo "Expected mkimage_kernel to be called with \"$expected\" but it was called with \"$saved_args\"" >&2
-exit 1
+return 1
 fi
 )
 }
+
+test_mkimage_kernel() {
+local kdata="/dev/zero"
+local expected="-A arm -O linux -T kernel -C none -a 0xdeadbeef -e 0xbaddcafe -n desc -d $kdata output"
+_test_mkimage_kernel "$kdata" "$expected" || exit 1
+}
 add_test test_mkimage_kernel
 
+test_mkimage_kernel_gzip() {
+local kdata="$(mktemp)"
+gzip < /dev/null > "$kdata"
+
+local expected="-A arm -O linux -T kernel -C gzip -a 0xdeadbeef -e 0xbaddcafe -n desc -d $kdata output"
+_test_mkimage_kernel "$kdata" "$expected" || exit 1
+rm -f "$kdata"
+}
+add_test test_mkimage_kernel_gzip
+
 test_mkimage_initrd() {
 (
 mkimage() {
-- 
2.20.1



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Bug#831003: support gzip'd kernel image

[dann frazier]

Package: flash-kernel
Version: 3.67
Tags: patch

flash-kernel currently always sets the compression type to "none" when
generating uImages. However, if the source vmlinuz file is gzip'd - as
is the case if you build the "Image.gz" kernel target - this will
prevent U-Boot from being able to boot it[1]. If the uImage is
generated with a compression type of "gzip", then it boots fine.

The attached patch checks the source image type and sets the
compression setting appropriately.

[1] At least, this is true on APM Mustang systems

diff -urpN flash-kernel-3.67/debian/changelog flash-kernel-3.68/debian/changelog
--- flash-kernel-3.67/debian/changelog	2016-06-20 00:20:31.0 -0600
+++ flash-kernel-3.68/debian/changelog	2016-07-13 09:33:53.714642651 -0600
@@ -1,3 +1,9 @@
+flash-kernel (3.68) UNRELEASED; urgency=medium
+
+  * Add support for gzip-compressed kernel images
+
+ -- dann frazier   Wed, 13 Jul 2016 09:22:49 -0600
+
 flash-kernel (3.67) unstable; urgency=medium
 
   [ Vagrant Cascadian ]
diff -urpN flash-kernel-3.67/functions flash-kernel-3.68/functions
--- flash-kernel-3.67/functions	2016-04-01 21:01:45.0 -0600
+++ flash-kernel-3.68/functions	2016-07-13 09:25:43.520547829 -0600
@@ -409,15 +409,31 @@ get_kernel_cmdline_defaults() {
 	echo "$LINUX_KERNEL_CMDLINE_DEFAULTS"
 }
 
+compress_type() {
+local file="$1"
+magic="$(od -x -N2 $file | head -1 | cut -d' ' -f2)"
+case $magic in
+	8b1f)
+	echo "gzip"
+	;;
+	*)
+	echo "none"
+	;;
+esac
+}
+
 mkimage_kernel() {
 	local kaddr="$1"
 	local epoint="$2"
 	local kdesc="$3"
 	local kdata="$4"
 	local uimage="$5"
+	local comp
+
+	comp="$(compress_type $kdata)"
 
 	printf "Generating kernel u-boot image... " >&2
-	mkimage -A arm -O linux -T kernel -C none -a "$kaddr" -e "$epoint" \
+	mkimage -A arm -O linux -T kernel -C $comp -a "$kaddr" -e "$epoint" \
 		-n "$kdesc" -d "$kdata" "$uimage" >&2 1>/dev/null
 	echo "done." >&2
 }
diff -urpN flash-kernel-3.67/test_functions flash-kernel-3.68/test_functions
--- flash-kernel-3.67/test_functions	2016-02-14 21:01:43.0 -0700
+++ flash-kernel-3.68/test_functions	2016-07-13 09:28:35.812630206 -0600
@@ -569,23 +569,40 @@ test_set_machine_id() {
 }
 add_test test_set_machine_id
 
-test_mkimage_kernel() {
+_test_mkimage_kernel() {
+local kdata="$1"
+local expected="$2"
 (
 mkimage() {
 saved_args="$@"
 }
 . "$functions"
 saved_args=""
-mkimage_kernel "0xdeadbeef" "0xbaddcafe" "desc" "input" "output" 2>/dev/null
-expected="-A arm -O linux -T kernel -C none -a 0xdeadbeef -e 0xbaddcafe -n desc -d input output"
+mkimage_kernel "0xdeadbeef" "0xbaddcafe" "desc" "$kdata" "output" 2>/dev/null
 if [ "$expected" != "$saved_args" ]; then
 echo "Expected mkimage_kernel to be called with \"$expected\" but it was called with \"$saved_args\"" >&2
-exit 1
+return 1
 fi
 )
 }
+
+test_mkimage_kernel() {
+local kdata="/dev/zero"
+local expected="-A arm -O linux -T kernel -C none -a 0xdeadbeef -e 0xbaddcafe -n desc -d $kdata output"
+_test_mkimage_kernel "$kdata" "$expected" || exit 1
+}
 add_test test_mkimage_kernel
 
+test_mkimage_kernel_gzip() {
+local kdata="$(mktemp)"
+gzip < /dev/null > "$kdata"
+
+local expected="-A arm -O linux -T kernel -C gzip -a 0xdeadbeef -e 0xbaddcafe -n desc -d $kdata output"
+_test_mkimage_kernel "$kdata" "$expected" || exit 1
+rm -f "$kdata"
+}
+add_test test_mkimage_kernel_gzip
+ 
 test_mkimage_initrd() {
 (
 mkimage() {