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

From: Thomas Gleixner
Date: Thu May 11 2017 - 17:18:08 EST


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.

Thanks,

tglx