Re: [PATCH AUTOSEL 5.14 38/99] KVM: PPC: Book3S HV: XICS: Fix mapping of passthrough interrupts

On 9/11/21 4:35 PM, Sasha Levin wrote:
> On Fri, Sep 10, 2021 at 07:48:18AM +0200, Cédric Le Goater wrote:
>> On 9/10/21 2:14 AM, Sasha Levin wrote:
>>> From: Cédric Le Goater <[email protected]>
>>>
>>> [ Upstream commit 1753081f2d445f9157550692fcc4221cd3ff0958 ]
>>>
>>> PCI MSIs now live in an MSI domain but the underlying calls, which
>>> will EOI the interrupt in real mode, need an HW IRQ number mapped in
>>> the XICS IRQ domain. Grab it there.
>>>
>>> Signed-off-by: Cédric Le Goater <[email protected]>
>>> Signed-off-by: Michael Ellerman <[email protected]>
>>> Link: https://lore.kernel.org/r/[email protected]
>>> Signed-off-by: Sasha Levin <[email protected]>
>>
>>
>> Why are we backporting this patch in stable trees ?
>>
>> It should be fine but to compile, we need a partial backport of commit
>> 51be9e51a800 ("KVM: PPC: Book3S HV: XIVE: Fix mapping of passthrough
>> interrupts") which exports irq_get_default_host().
> 
> Or, I can drop it if it makes no sense?

Yes I would. 

It makes sense only with the full patchset, the one reworking PCI MSI 
support in the PPC pSeries and PowerNV platforms.

Thanks,

C.