On Thu, Jan 11, 2018 at 02:22:00AM +0000, Maximilian Pichler wrote: > On Wed, Jan 10, 2018 at 6:50 PM, Mike Larkin <mlar...@azathoth.net> wrote: > >> > My question is: Can OpenBSD be told initialize the software from the > >> > hardware clock again after the system is booted? > > > This does occur on occasion; for example, when running an OpenBSD vmm(4) > > guest, vmd(8) will notify the guest to resynch the clock from the RTC > > after the host resumes from suspend/hibernate (actually, "any time > > the host clock varies from more than 5s since it was last read by vmd(8"), > > but that practically means "only during suspend/hibernate resumes"). > > > > If the OP was looking for code to do this for whatever reason, it's done > > via vmmci(4). > > In fact this is precisely the use case I had in mind, except for that > instead of inside vmm OpenBSD is running in Virtualbox on Mac OS. The > clock seems to drift randomly and is off significantly after > suspend/hibernate. > > Following your hint at vmmci and looking at > https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/dev/pv/vmmci.c.diff?r1=1.2&r2=1.3&f=h > it looks like inittodr(9) would reinitialize the software clock. > However it seems to be available inside the kernel only. Is there no > way to do this from userland? > > Thanks! >
not that I know of.
