Hi Stephen, [+Marco and Boris] On Fri, May 22, 2020 at 03:31:19AM +1000, Stephen Rothwell wrote: > After merging the tip tree, all my linux-next builds took signficantly > longer and used much more memory. In some cases, builds would seg fault > due to running out of memory :-( > > I have eventaully bisected it to commit > > cdd28ad2d811 ("READ_ONCE: Use data_race() to avoid KCSAN instrumentation") > > For my (e.g.) x86_64 allmodconfig builds (cross compiled on PowerPC le, > -j80) the elapsed time went from around 9 minutes to over 17 minutes > and the maximum resident size (as reported by /usr/bin/time) from around > 500M to around 2G (I saw lots of cc1 processes over 2G in size). > > For tomorrow's linux-next (well, later today :-() I will revert that > commit (and its child) when I merge the tip tree. Sorry about that, seems we can't avoid running into compiler problems with this lot. The good news is that there's a series to fix this here: https://lore.kernel.org/r/20200521142047.169334-1-elver@xxxxxxxxxx so hopefully this be fixed in -tip soon (but I agree that reverting the thing in -next in the meantime makes sense). Will