Re: [patch 3/8] PCI/MSI: Enforce that MSI-X table entry is masked for update

From: Bjorn Helgaas
Date: Thu Jul 22 2021 - 17:47:00 EST

On Wed, Jul 21, 2021 at 09:11:29PM +0200, Thomas Gleixner wrote:
> The specification states:

Maybe add "(PCIe r5.0, sec"

> For MSI-X, a function is permitted to cache Address and Data values
> from unmasked MSI-X Table entries. However, anytime software unmasks a
> currently masked MSI-X Table entry either by clearing its Mask bit or
> by clearing the Function Mask bit, the function must update any Address
> or Data values that it cached from that entry. If software changes the
> Address or Data value of an entry while the entry is unmasked, the
> result is undefined.