Re: [RFC 0/2] PCI: acpiphp: workaround race between hotplug and SCSI_SCAN_ASYNC job

[Rafael J. Wysocki]

On Wed, Dec 13, 2023 at 7:11 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> On Wed, Dec 13, 2023 at 01:36:12AM +0100, Igor Mammedov wrote:
> > Hacks to mask a race between HBA scan job and bridge re-configuration(s)
> > during hotplug.
> >
> > I don't like it a bit but it something that could be done quickly
> > and solves problems that were reported.
>
> I agree, I don't like it either.  Adding a 1s delay doesn't address
> the real problem, and putting in a band-aid like this means the real
> problem would likely never be addressed.
>
> At this point the best option I see is to revert these:
>
>   cc22522fd55e2 ("PCI: acpiphp: Use pci_assign_unassigned_bridge_resources() only for non-root bus")
>   40613da52b13f ("PCI: acpiphp: Reassign resources on bridge if necessary")
>
> I hate the fact that reverting them would mean the root bus hotplug
> and ACPI bus check notifications would become issues again.
>
> But keeping these commits even though they add a new different problem
> that breaks things for somebody else seems worse to me.

Agreed.