> Date: Tue, 25 Dec 2018 09:48:10 +0100 > From: Landry Breuil <lan...@openbsd.org> > > On Sun, Dec 23, 2018 at 09:20:11PM +0100, Mark Kettenis wrote: > > > Date: Sun, 23 Dec 2018 19:35:02 +0100 (CET) > > > From: Mark Kettenis <mark.kette...@xs4all.nl> > > > > > > > Date: Sun, 23 Dec 2018 12:26:17 +0100 (CET) > > > > From: Mark Kettenis <mark.kette...@xs4all.nl> > > > > > > > > That's a very good find. I think there still is a potential race in > > > > your diff on MP systems since you save the bits before removing the > > > > PTE from the has tables. I'll see if I can come up with a better diff. > > > > > > So here is the diff I propose instead. This zaps the PTE before > > > unlinking. At that point the PTED_VA_MANAGED_M flag is still set so > > > the MOD/REF accounting will happen. A process running on the other > > > CPU can't put the PTE back into the hash as we still hold the lock on > > > the pmap. > > > > > > Bootstrapping clang with this diff, and things are still running even > > > though I've hit swap. I'll give this a spin on an MP machine as well. > > > > I fear sombody else needs to test on an MP machine as my dual G4 > > doesn't boot anymore :(. > > I'll put this diff on macppc-*.p in the next bulk (in some days), both > are MP. Maybe it'll fix the random ICEs when building c++ monsters, > which probably hit swap as there's only 2Gb physmem...
Theo put the diff in snaps. And yes, it will almost certainly fix some of the random ICEs.
