Re: [PATCH 4.4 16/60] x86/ioapic: Restore IO-APIC irq_chip retrigger callback

[Greg Kroah-Hartman]

On Thu, May 11, 2017 at 11:17:59PM +0200, Thomas Gleixner wrote:
> On Thu, 11 May 2017, Ben Hutchings wrote:
> 
> > On Thu, 2017-05-11 at 16:12 +0200, Greg Kroah-Hartman wrote:
> > > 4.4-stable review patch.  If anyone has any objections, please let me know.
> > > 
> > > ------------------
> > > 
> > > From: Ruslan Ruslichenko <rruslich@xxxxxxxxx>
> > > 
> > > commit a9b4f08770b415f30f2fb0f8329a370c8f554aa3 upstream.
> > > 
> > > commit d32932d02e18 removed the irq_retrigger callback from the IO-APIC
> > > chip and did not add it to the new IO-APIC-IR irq chip.
> > > 
> > > There is no harm because the interrupts are resent in software when the
> > > retrigger callback is NULL, but it's less efficient. So restore them.
> > 
> > Sounds like it's not important enough for stable, then?
> 
> Actually that changelog is wrong, but this commit got reverted because it
> triggered some crap code.
> 
> After we fixed that it was brought back with:
> 
>       020eb3daaba2857b32c4cf4c82f503d6a00a67de
> 
> The related fixes are:
> 
>     47512cfd0d7a8bd6ab71d01cd89fca19eb2093eb
>     6cf18e6927c0b224f972e3042fb85770d63cb9f8
> 
> which are both tagged for stable as well.

Those both are in stable already, so this should be safe to add, so I'll
leave it as-is.

thanks,

greg k-h