On Tue, Sep 5, 2017 at 11:15 PM, Christoph Hellwig <h...@lst.de> wrote: > On Wed, Sep 06, 2017 at 12:13:38PM +0800, Yu Chen wrote: >> I agree, the driver could be rewritten, but it might take some time, so >> meanwhile I'm looking at also other possible optimization. > > Which driver are we talking about anyway? Let's start looking at it > and fix the issue there.
As far as I understand, it's already fixed there: commit 7c9ae7f053e9e896c24fd23595ba369a5fe322e1 Author: Carolyn Wyborny <carolyn.wybo...@intel.com> Date: Tue Jun 20 15:16:53 2017 -0700 i40e: Fix for trace found with S4 state This patch fixes a problem found in systems when entering S4 state. This patch fixes the problem by ensuring that the misc vector's IRQ is disabled as well. Without this patch a stack trace can be seen upon entering S4 state. However this seems like something that should be handled generically in the irq-core especially since commit c5cb83bb337c "genirq/cpuhotplug: Handle managed IRQs on CPU hotplug" was headed in that direction. It's otherwise non-obvious when a driver needs to release and re-acquire interrupts or be reworked to use managed interrupts.