please revert commit ce8556cca6 "kbuild: verify that $DEPMOD is installed" introduced in v4.18.4.
This patch requires that /sbin/depmod is installed and installable on the build host.
But not all build hosts for cross compiling Linux are Linux systems and are able to provide a working port of depmod, especially at the file patch /sbin/depmod.
I use, for example, a Darwin system to cross compile Linux and I run depmod -a on the embedded system once, after installing a new Linux kernel there.
I have no problem with seeing a warning, but aborting the build process is IMHO a bad idea since the previous behaviour didn't harm many people as far as I see. Probably 99% of people compiling Linux kernels do that on Linux and 99% of those have depmod installed for optimal operation of their build host. So IMHO printing the warning is good enough.
BR and thanks, Nikolaus Schaller
On 08/22/2018 11:53 AM, H. Nikolaus Schaller wrote:
Thanks for the report and sorry about the problem.
I'm OK with changing the error to a warning. Does the patch below work for you?
thanks. --- From: Randy Dunlap rdunlap@infradead.org
When $DEPMOD is not found, only print a warning instead of exiting with an error message and error status.
E.g.: Warning: 'make modules_install' requires /sbin/depmod. Please install it. This is probably in the kmod package. ../scripts/depmod.sh: line 44: /sbin/depmod: No such file or directory make[1]: *** [/home/rdunlap/lnx/lnx-418/Makefile:1244: _modinst_post] Error 127 make: *** [Makefile:146: sub-make] Error 2
Signed-off-by: Randy Dunlap rdunlap@infradead.org Reported-by: H. Nikolaus Schaller hns@goldelico.com --- scripts/depmod.sh | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- lnx-418.orig/scripts/depmod.sh +++ lnx-418/scripts/depmod.sh @@ -15,9 +15,8 @@ if ! test -r System.map ; then fi
if [ -z $(command -v $DEPMOD) ]; then - echo "'make modules_install' requires $DEPMOD. Please install it." >&2 + echo "Warning: 'make modules_install' requires $DEPMOD. Please install it." >&2 echo "This is probably in the kmod package." >&2 - exit 1 fi
# older versions of depmod require the version string to start with three
On Wed, Aug 22, 2018 at 4:35 PM Randy Dunlap rdunlap@infradead.org wrote:
Why would one want a warning on a host that never runs "make modules_install"? Can this check be only done when we actually try to install modules?
Thanks.
On 08/22/2018 05:39 PM, Dmitry Torokhov wrote:
So Nikolaus: how do you provoke this problem that you are reporting? It's not just a theoretical problem, is it?
The way that I read the top-level Makefile, this check for $DEPMOD only happens when you run "make modules_install".
Hi Randy,
Yes, we run on the build host
make letux_defconfig dtbs uImage INSTALL_MOD_PATH=/tmp/kernel-modules-$$ modules modules_install
and then scp the files from /tmp/kernel-modules-$$ to the embedded device. Or pack into some installable file setfor download on our server.
So we run modules_install on the build host as well to copy the modules into the correct hierarchy and give it the correct lib/modules/<kernel_release> prefix.
I would have to duplicate this what module_install does in some wrapper script.
BTW: it is a standard technique described by others:
http://labs.isee.biz/index.php/The_Linux_kernel#IGEP_Boards_based_on_Texas_I...
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules_install INSTALL_MOD_PATH=/media/user/rootfs
http://en.gnublin.org/index.php/Kernel_compile_%2B_Module_installation#Compi...
mkdir kernel_archiv make modules_install INSTALL_MOD_PATH=kernel_archiv cp arch/arm/boot/zImage kernel_archiv cd kernel_archiv tar cfvz kernel.tar.gz zImage lib/
All these descriptions will now break if run on a host without /sbin/depmod installed.
BR and thanks, Nikolaus
2018-08-23 10:07 GMT+09:00 Randy Dunlap rdunlap@infradead.org:
Unless I am misunderstanding, he wants to use "make modules_install" just for copying modules.
Then, he will run depmod on the target system later.
Hi Randy,
2018-08-23 8:33 GMT+09:00 Randy Dunlap rdunlap@infradead.org:
'exit 0' is missing here.
This shell script would fail, then abort the build process.
On Thu, Aug 23, 2018 at 05:38:27PM +0900, Masahiro Yamada wrote:
May I suggest the following implementation:
diff -U0 scripts/depmod.sh ~/tmp/depmod.sh --- scripts/depmod.sh 2018-08-10 17:14:19.036349222 +0300 +++ /home/sasha/tmp/depmod.sh 2018-08-23 18:07:23.486048827 +0300
# 'if' block may be omitted here. If System.map isn't there and isn't readable, 'exit 0'. @@ -13,3 +13 @@ -if ! test -r System.map ; then - exit 0 -fi +test -r System.map || exit 0
# Have the 'if' test statement syntax conform with the remainder of the script, which uses 'if test' rather then the 2nd form of the test utility, i.e. '[ expr ]'. # In my view, the use of the negation operator, '!', makes the intent clearer, and reads, 'if $DEPMOD not found', rather then 'if the length of $DEPMOD is zero'. @@ -17 +15 @@ -if [ -z $(command -v $DEPMOD) ]; then +if test ! $(command -v $DEPMOD); then @@ -20 +18 @@ - exit 1 + exit 0
[Sample run] # Testing for a non-existant utility: % if test ! $(command -v cmd); then echo cmd not found; fi % cmd not found
# Testing for a existing utility: % if test ! $(command -v ed); then echo ed not found; fi
% if test $(command -v ed); then echo ed found; fi % ed found
From: Randy Dunlap rdunlap@infradead.org
When $DEPMOD is not found, only print a warning instead of exiting with an error message and error status.
Warning: 'make modules_install' requires /sbin/depmod. Please install it. This is probably in the kmod package.
Signed-off-by: Randy Dunlap rdunlap@infradead.org --- v2: add missing "exit 0" and update the commit message (no Error).
scripts/depmod.sh | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- lnx-418.orig/scripts/depmod.sh +++ lnx-418/scripts/depmod.sh @@ -15,9 +15,9 @@ if ! test -r System.map ; then fi
if [ -z $(command -v $DEPMOD) ]; then - echo "'make modules_install' requires $DEPMOD. Please install it." >&2 + echo "Warning: 'make modules_install' requires $DEPMOD. Please install it." >&2 echo "This is probably in the kmod package." >&2 - exit 1 + exit 0 fi
# older versions of depmod require the version string to start with three
linux-stable-mirror@lists.linaro.org
-
Alexander Kapshuk -
Dmitry Torokhov -
Greg KH -
H. Nikolaus Schaller -
Masahiro Yamada -
Randy Dunlap