A patch is applied to fix builds with 4.8 kernels (specifically, 4.8 linux-libc-headers, as it doesn't use actual kernel headers), but doing so breaks builds with older linux-libc-headers. This isn't an issue for internal toolchain builds, as we only keep around a single linux-libc-headers version, but the external toolchain has its own, and I haven't seen any updated to 4.8 yet, so this effectively breaks ppp builds for all current external toolchains. It'd be nice if we could find a fix that worked for kernels earlier and later than 4.8 both, so we don't have to decide whether to revert the patch in meta-sourcery based on the particulars of the external toolchain in use.
Updated the meta-sourcery workaround to grab the kernel version from the external toolchain sysroot and remove the patch based on that, so this is low priority.
It does not only break it for external toolchains, but also if you set LINUXLIBCVERSION to something < 4.8 for internal toolchains with morty. I took your ppp_2.4.7.bbappend, hacked it a bit and added it to my meta layer so it works now with an internal toolchain, but a LINUXLIBCVERSION before 4.4 as well: KERNEL_48_PATCH = "file://ppp-fix-building-with-linux-4.8.patch" SRC_URI_remove := "${@'${KERNEL_48_PATCH}' if [int(i) for i in ('${LINUXLIBCVERSION}'.replace('%', '') or '0.0').split('.')] < [4, 8] else ''}"
should be but a LINUXLIBCVERSION before 4.8 as well:
(In reply to comment #2) > It does not only break it for external toolchains, but also if you set > LINUXLIBCVERSION to something < 4.8 for internal toolchains with morty. > > I took your ppp_2.4.7.bbappend, hacked it a bit and added it to my meta > layer so it works now with an internal toolchain, but a LINUXLIBCVERSION > before 4.4 as well: > > KERNEL_48_PATCH = "file://ppp-fix-building-with-linux-4.8.patch" > SRC_URI_remove := "${@'${KERNEL_48_PATCH}' if [int(i) for i in > ('${LINUXLIBCVERSION}'.replace('%', '') or '0.0').split('.')] < [4, 8] else > ''}" So we specify the patch to the kernel 4.8 can solve the problem.
This patch should only be applied when a 4.8 (or maybe newer) kernel is used and certainly makes a problem for 4.4 kernels.
Fixed in: morty: http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?h=morty&id=97d7e4ca751e6010da97e7f082dd13230fe3ef10 master: http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=6ee124905f5241ea2b96822111a08e1463d319d2