On Tue, 2017-08-08 at 08:43:15 UTC, "Gautham R. Shenoy" wrote: > From: "Gautham R. Shenoy" <e...@linux.vnet.ibm.com> > > Currently, we use the opal call opal_slw_set_reg() to inform the > Sleep-Winkle Engine (SLW) to restore the contents of some of the > Hypervisor state on wakeup from deep idle states that lose full > hypervisor context (characterized by the flag > OPAL_PM_LOSE_FULL_CONTEXT). > > However, the current code has a bug in that if opal_slw_set_reg() > fails, we don't disable the use of these deep states (winkle on > POWER8, stop4 onwards on POWER9). > > This patch fixes this bug by ensuring that if programing the > sleep-winkle engine to restore the hypervisor states in > pnv_save_sprs_for_deep_states() fails, then we exclude such states by > clearing the OPAL_PM_LOSE_FULL_CONTEXT flag from > supported_cpuidle_states. As a result POWER8 will be prevented from > using winkle for CPU-Hotplug, and POWER9 will put the offlined CPUs to > the default stop state when available. > > Further, we ensure in the initialization of the cpuidle-powernv driver > to only include those states whose flags are present in > supported_cpuidle_states, thereby skipping OPAL_PM_LOSE_FULL_CONTEXT > states when they have been disabled due to stop-api failure. > > Fixes: 1e1601b38e6 ("powerpc/powernv/idle: Restore SPRs for deep idle > states via stop API.") > > Signed-off-by: Gautham R. Shenoy <e...@linux.vnet.ibm.com>
Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/785a12afdb4a52903447fd890633c8 cheers