The other oddity, running the guest with 1 cpu always works for me in the cases where it failed before.
On Wed, Dec 14, 2016 at 5:37 PM, Ryan Harper <ryan.har...@canonical.com> wrote: > > > On Wed, Dec 14, 2016 at 4:31 PM, Seth Forshee < > seth.forshee...@canonical.com> wrote: > >> Looking at kernel 4.9, the RTC_UIE_ON ioctl sets an alarm via the >> cmos_rtc driver. This does a couple of things. >> >> 1. Disables the CMOS RTC alarm interrupt, writes an alarm time to the >> CMOS RTC, then enables the alarm interrupt. >> >> 2. When configured to emulate an RTC using the HPET (which our kernel >> is), makes sure HPET timer 1 is initialized for RTC emulation. >> >> Based on this I looked at the diffs for hw/timer/mc146818rtc.c (which >> seems to be the CMOS RTC device) and hw/timer/hpet.c between the two >> qemu versions. The differences all look pretty trivial, I don't see >> anything which looks like it would have fixed the problem. >> > > It's a guest kernel + qemu interaction. In the past, there was an issue > w.r.t > ensuring RTC interrupts were being delivered; that's what's currently > broken. > > Comparing: grep rtc /proc/interrupts where it works (Trusty) vs failed, > and you can see > that we get at most a few interrupts to the RTC device. > > There isn't a whole lot of change to qemu's RTC between 2.5 and 2.6.1 in > yakkety > So, I need to see if running yakkety qemu on Xenial fixes things as well > so we can > continue to narrow down where the regression was introduced. > > >> >> -- >> You received this bug notification because you are subscribed to qemu in >> Ubuntu. >> https://bugs.launchpad.net/bugs/1649718 >> >> Title: >> Linux rtc self test fails in a VM under xenial >> >> To manage notifications about this bug go to: >> https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1649718/ >> +subscriptions >> > > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1649718 Title: Linux rtc self test fails in a VM under xenial To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1649718/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs