Hi, On Thu, May 28, 2020 at 4:44 AM Maulik Shah <mkshah@xxxxxxxxxxxxxx> wrote: > > Hi Doug, > > During suspend-resume with this change on sc7180 using latest > linux-next, below warning was reported. > > WARNING: CPU: 0 PID: 5324 at kernel/time/timekeeping.c:754 > ktime_get+0x94/0x9c > ktime_get+0x94/0x9c > write_tcs_reg_sync+0x4c/0x130 > tcs_invalidate+0x64/0xa4 > rpmh_rsc_invalidate+0x20/0x38 > rpmh_flush+0x58/0x1ec > rpmh_rsc_cpu_pm_callback+0xe4/0x144 > notifier_call_chain+0x58/0x90 > __atomic_notifier_call_chain+0x48/ > cpu_pm_notify+0x40/0x6c > cpu_pm_enter+0x34/0x7c > cpu_pm_suspend+0x10/0x20 > syscore_suspend+0x128/0x2a4 > suspend_devices_and_enter+0x5e0/0x8a0 > > This seems to be because timekeeping is already suspend by this time. Thanks for the report. I posted: https://lore.kernel.org/r/20200528074530.1.Ib86e5b406fe7d16575ae1bb276d650faa144b63c@changeid I think there are still a bunch of not-yet-landed patches needed for suspend-resume so I only confirmed that the code still works OK for the idle case. Hopefully you can confirm s2r is good, though I'd believe it should be exactly the same. I'm 99% sure that udelay() still works fine even when timekeeping is suspended. -Doug
