Hi Randy, > Am 23.08.2018 um 03:07 schrieb Randy Dunlap <rdunlap@xxxxxxxxxxxxx>: > > On 08/22/2018 05:39 PM, Dmitry Torokhov wrote: >> On Wed, Aug 22, 2018 at 4:35 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: >>> >>> On 08/22/2018 11:53 AM, H. Nikolaus Schaller wrote: >>>> 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. >>> >>> 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? >> >> 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? > > > 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". 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_Instruments_.C2.A0Processors 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#Compile_the_modules 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
