Re: [PATCH 0/3] arm64: Fix cpuidle with pseudo-NMI enabled
From: Sudeep Holla <hidden>
Date: 2021-06-10 17:45:53
On Thu, Jun 10, 2021 at 05:28:23PM +0100, Lorenzo Pieralisi wrote:
On Tue, Jun 08, 2021 at 06:27:12PM +0100, Marc Zyngier wrote:quoted
It appears that although cpu_do_idle() is correctly dealing with the PMR/DAIF duality, the PSCI cpu-suspend code has been left unaware of it. On a system that uses PSCI for idle (such as the Ampere Altra I have access to), the kernel dies as soon as it enters idle (interrupts are off at the GIC CPU interface level). Boo.
[...]
I wonder whether this arm_cpuidle_{save,restore}_context() should
be moved into the gic_cpu_pm_notifier() itself - which would
solve also the PSCI suspend issue Sudeep raised - it would be
a bit ugly though (CPU PM notifiers are run in S2R and CPUidle+1 if possible, I hadn't fully understood the issue to make this suggestion. But yes if possible, we must to honour the abstraction even though PSCI is the only user 😄.
automatically and this would work for any S2R/CPUidle backend other than PSCI even though that does not/will never exist on arm64 ;-))
I almost wrote the same thing in my earlier email and deleted 😉 before sending. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel