[PATCH 2/3] powerpc/pci: unmap legacy INTx interrupts of passthrough IO adapters

[Cédric Le Goater]

Hello Michael,

On 4/29/20 9:51 AM, Cédric Le Goater wrote:
> When a passthrough IO adapter is removed from a pseries machine using
> hash MMU and the XIVE interrupt mode, the POWER hypervisor, pHyp,
> expects the guest OS to have cleared all page table entries related to
> the adapter. If some are still present, the RTAS call which isolates
> the PCI slot returns error 9001 "valid outstanding translations" and
> the removal of the IO adapter fails.
> 
> INTx interrupt numbers need special care because Linux maps the
> interrupts automatically in the Linux interrupt number space if they
> are presented in the device tree node describing the IO adapter. These
> interrupts are not un-mapped automatically and in case of an hot-plug
> adapter, the PCI hot-plug layer needs to handle the cleanup to make
> sure that all the page table entries of the XIVE ESB pages are
> cleared.

It seems this patch needs more digging to make sure we are handling
the IRQ unmapping in the correct PCI handler. Could you please keep
it back for the moment ? 

Thanks,

C.