Re: [patch 0/8] PCI/MSI, x86: Cure a couple of inconsistencies

Thomas Gleixner
2021-07-27T20:39:01Z

Bjorn,

On Thu, Jul 22 2021 at 16:43, Bjorn Helgaas wrote:
> On Wed, Jul 21, 2021 at 09:11:26PM +0200, Thomas Gleixner wrote:
>> A recent discussion about the PCI/MSI management for virtio unearthed a
>> violation of the MSI-X specification vs. writing the MSI-X message: under
>> certain circumstances the entry is written without being masked.
>>
>> While looking at that and the related violation of the x86 non-remapped
>> interrupt affinity mechanism a few other issues were discovered by
>> inspection.
>>
>> The following series addresses these.
>>
>> Note this does not fix the virtio issue, but while staring at the above
>> problems I came up with a plan to address this. I'm still trying to
>> convince myself that I can get away without sprinkling locking all over the
>> place, so don't hold your breath that this will materialize tomorrow.
>>
>> The series is also available from git:
>>
>> git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git irq/msi
>>
>> Thanks,
>>
>> tglx
>> ---
>> arch/x86/kernel/apic/io_apic.c | 6 +-
>> arch/x86/kernel/apic/msi.c | 11 +++-
>> arch/x86/kernel/hpet.c | 2
>> drivers/pci/msi.c | 98 +++++++++++++++++++++++++++--------------
>> include/linux/irq.h | 2
>> kernel/irq/chip.c | 5 +-
>> 6 files changed, 85 insertions(+), 39 deletions(-)
>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com> for the PCI pieces.
>
> I'm happy to take the whole series via PCI, given an x86 ack. Or you
> can merge with my ack.

Let me repost it first with the various review comments fixed. I'm also
having a fix for the VFIO muck in the pipeline which will be based on
this and also requires changes to the irq core. Let me think about the
best way to get this routed.

Thanks,

tglx