On Wed, Oct 16, 2019 at 12:39:11PM +0200, Thomas Gleixner wrote: > On Wed, 16 Oct 2019, Vincenzo Frascino wrote: > > < Trim 250+ lines ( 3+ pages) of pointlessly wasted electrons > > > > > --- a/init/Kconfig > > > +++ b/init/Kconfig > > > @@ -1096,6 +1096,13 @@ config UTS_NS > > > In this namespace tasks see different info provided with the > > > uname() system call > > > > > > +config TIME_NS > > > + bool "TIME namespace" > > > + default y > > > > Having CONFIG_TIME_NS "default y" makes so that the option is selected even on > > the architectures that have no support for time namespaces. > > The direct consequence is that the fallbacks defined in this patch are never > > selected and this ends up in kernel compilation errors due to missing symbols. > > > > The error below shows what happens on arm64 (similar behavior on other > > architectures): > > > > aarch64-linux-gnu-ld: kernel/time/namespace.o: in function `timens_on_fork': > > kernel/time/namespace.c:321: undefined reference to `vdso_join_timens' > > > > My proposal is to keep TIME_NS "default n" (just remove "default y"), let the > > architectures that enable time namespaces select it and make CONFIG_TIME_NS > > select GENERIC_VDSO_TIME_NS if arch has HAVE_GENERIC_VDSO. > > Nah. > > config TIME_NS > bool "TIME namespace" > depends on GENERIC_VDSO_TIME_NS I was thinking to fix this by the same way with a small difference. If GENERIC_GETTIMEOFDAY isn't set, it should be safe to allow enabling TIME_NS. In this case, clock_gettime works via system call and we don't have arch-specific code in this case. Does this sound reasonable? depends on (!GENERIC_GETTIMEOFDAY || GENERIC_VDSO_TIME_NS) Thanks, Andrei _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers