Re: [patch 1/8] PCI/MSI: Enable and mask MSIX early

From: Thomas Gleixner
Date: Tue Jul 27 2021 - 16:33:42 EST


On Thu, Jul 22 2021 at 16:43, Bjorn Helgaas wrote:
> s/MSIX/MSI-X/ in subject

Sure.

> On Wed, Jul 21, 2021 at 09:11:27PM +0200, Thomas Gleixner wrote:
>> The ordering of MSI-X enable in hardware is disfunctional:
>
> s/disfunctional/dysfunctional/, isn't English wonderful ;)

Yes and I'm never going to master it.

>> 1) MSI-X is disabled in the control register
>> 2) Various setup functions
>> 3) pci_msi_setup_msi_irqs() is invoked which ends up accessing
>> the MSI-X table entries
>> 4) MSI-X is enabled and masked in the control register with the
>> comment that enabling is required for some hardware to access
>> the MSI-X table
>>
>> #4 obviously contradicts #3. The history of this is an issue with the NIU
>
> Annoyingly, if you "git rebase" and reword this commit log, it drops
> this line and the one a few lines below because they start with "#".
> Should be obvious, but took me a few iterations to see what was
> happening.

Cute.

Thanks,

tglx