On 13.03.2024 15:35, Sudeep Holla wrote: > 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. I can fully reproduce this issue on Khadas VIM3 and Odroid-N2 boards. Both Meson A311D SoC based. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
