| Summary: | Cannot use linux kernel extensions from external tree (building zfs into kernel) | ||
|---|---|---|---|
| Product: | buildroot | Reporter: | mscdex <mscdex> |
| Component: | Other | Assignee: | unassigned |
| Status: | RESOLVED INVALID | ||
| Severity: | normal | CC: | buildroot, yann.morin.1998 |
| Priority: | P5 | ||
| Version: | 2024.02.1 | ||
| Target Milestone: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Host: | Target: | ||
| Build: | |||
Is it possible that you have `include */*.mk` in your external.mk? This will include your `linux/linux-ext-zfs-inkernel.mk` in the "main" buildroot include, but it should only be included in the linux-extensions-specific section in buildroot linux/linux.mk:
include $(sort $(wildcard $(foreach ext,$(BR2_EXTERNAL_DIRS), \
$(ext)/linux/linux-ext-*.mk)))
mscdex, All, You are calling the autotools-package macro in your linux externsion; that is going to create an actual package, which is what is actually causing you trouble. The linux-ext file should be limited exactly to defining the linux extension. Downloading the sources for the extension should be done in a separate package. See for example the fbtft linux extension, which is simple enough to be a good example. Regards, Yann E. MORIN. |
I'm wanting to build zfs into the kernel, so after reading through the documentation it seemed like the best way to go about it would be through Buildroot's Linux kernel extension mechanism. I already have an existing, working external tree, so according to the documentation I added a `linux/Config.ext.in` and `linux/linux-ext-zfs-inkernel.mk` to my external tree. Re-running `make menuconfig` and navigating to the Linux Extensions section shows both the built-in Buildroot extensions and my new extension. However, after I select my extension and save the Buildroot configuration, just about every make target except `menuconfig` fails with: linux/linux.mk:646: *** Package 'linux' defined a second time in 'linux/'; previous definition was in '/home/foo/buildroot-external/linux/'. Stop. make: *** [Makefile:23: _all] Error 2 I tried explicitly adding a reference to the Config.ext.in in my external tree's Config.in and adding a reference to the linux-ext-zfs-inkernel.mk in my external tree's external.mk, but that did not make any difference. For what it's worth here are the contents of the two files (there may be issues with them as I obviously haven't been able to test them yet): linux/Config.ext.in: config BR2_LINUX_KERNEL_EXT_ZFS_INKERNEL bool "In-kernel ZFS" help In-kernel ZFS module linux/linux-ext-zfs-inkernel.mk: ZFS_INKERNEL_VERSION = 2.2.2 ZFS_INKERNEL_SOURCE = https://github.com/openzfs/zfs/releases/download/zfs-$(ZFS_INKERNEL_VERSION) ZFS_INKERNEL_INSTALL_STAGING = NO ZFS_INKERNEL_INSTALL_TARGET = NO define ZFS_INKERNEL_COPY_BUILTIN cd $(ZFS_INKERNEL_BUILDDIR) && ./copy-builtin $(LINUX_DIR) endef ZFS_INKERNEL_POST_CONFIGURE_HOOKS += ZFS_INKERNEL_COPY_BUILTIN LINUX_EXTENSIONS += zfs-inkernel ZFS_INKERNEL_CONF_OPTS = \ --with-linux=$(LINUX_DIR) \ --enable-linux-builtin ZFS_INKERNEL_MAKE = true $(eval $(autotools-package))