On Tue, 28 Jul 2020 at 22:40, Nitesh Narayan Lal <nitesh@xxxxxxxxxx> wrote: > > Hi, > > I have recently come across an RCU trace with the 5.8-rc7 kernel that has the > debug configs enabled while installing a VM on a CPU that is listed under > nohz_full. > > Based on some of the initial debugging, my impression is that the issue is > triggered because of the fastpath that is meant to optimize the writes to x2APIC > ICR that eventually leads to a virtual IPI in fixed delivery mode, is getting > invoked from the quiescent state. I still can reproduce this after removing the ipi/timer fastpath codes, anyway, I will have a look.
