powerpc/vio: dispose of virq mapping on vdevice unregister

[Michael Ellerman]

On Fri, 2017-09-29 at 00:19:20 UTC, Tyrel Datwyler wrote:
> When a vdevice is DLPAR removed from the system the vio subsystem doesn't
> bother unmapping the virq from the irq_domain. As a result we have a virq
> mapped to a hardware irq that is no longer valid for the irq_domain. A side
> effect is that we are left with /proc/irq/<irq#> affinity entries, and
> attempts to modify the smp_affinity of the irq will fail.
> 
> In the following observed example the kernel log is spammed by
> ics_rtas_set_affinity errors after the removal of a VSCSI adapter. This is a
> result of irqbalance trying to adjust the affinity every 10 seconds.
> 
> rpadlpar_io: slot U8408.E8E.10A7ACV-V5-C25 removed
> ics_rtas_set_affinity: ibm,set-xive irq=655385 returns -3
> ics_rtas_set_affinity: ibm,set-xive irq=655385 returns -3
> 
> This patch fixes the issue by calling irq_dispose_mapping() on the virq of the
> viodev on unregister.
> 
> Signed-off-by: Tyrel Datwyler <tyreld at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/b8f89fea599d91e674497aad572613

cheers