On Tue, Mar 12, 2024 at 05:55:49PM +0000, Catalin Marinas wrote: > On Tue, Mar 12, 2024 at 10:06:06AM -0700, Christoph Lameter (Ampere) wrote: > > On Mon, 11 Mar 2024, Christoph Lameter (Ampere) wrote: > > > > > This could be an issue in the ARM64 arch code itself where there maybe > > > an assumption elsewhere that a cpumask can always store up to NR_CPU > > > cpus and not only nr_cpu_ids as OFFSTACK does. > > > > > > How can I exercise the opp driver in order to recreate the problem? > > > > > > I assume the opp driver is ARM specific? x86 defaults to OFFSTACK so if > > > there is an issue with OFFSTACK in opp then it should fail with kernel > > > default configuration on that platform. > > > > I checked the ARM64 arch sources use of NR_CPUS and its all fine. > > > > Also verified in my testing logs that CONFIG_PM_OPP was set in all tests. > > > > No warnings in the kernel log during those tests. > > > > How to reproduce this? > > I guess you need a platform with a dts that has an "operating-points-v2" > property. I don't have any around. > > Sudeep was trying to trigger this code path earlier, not sure where he > got to. I did try to trigger this on FVP by adding OPPs + some hacks to add dummy clock provider to successfully probe this driver. I couldn't hit the issue reported 🙁. It could be that with the hardware clock/regulator drivers, it take a different path in OPP core. -- Regards, Sudeep
