Re: [PATCH v5 00/14] PCI: Resource placement algorithm fixes

[Mario Limonciello]

> The regression is the same genoa iomem blackhole we discussed in the v3
> thread:
>
> https://lore.kernel.org/linux-pci/20261013130948.6231-9-ilpo.jarvinen@xxxxxxxxxxxxxxx
> /
>
> There were multiple possible possible ways to quirk this and it comes down
> to which one you (Bjorn) prefer. I just left my quirk patch out of these
> v4 and v5 series because it seemed the least likely to be the one taken.
>
> If you want me to test a specific quirk approach on the affected system,
> just let me know. I already did test reverting your change that freed the
> e820 reserved regions for iomem use and that did prevent the regression.

Yeah with any luck our best bet for everyone is reverting commit 
07eab0901ede ("efi/x86: Remove EfiMemoryMappedIO from E820 map").

> (I now seem to realize I forgot to include Mario while sending v5. I've
> added him to this now.)
>
> Mario was willing to pursue contacting the reporters of the earlier
> problems with a pre-prepared branch to test to see if my placement series
> could resolve the issues reported (earlier). Depending the results of that
> test, we might have yet another way to quirk it.
>
> Mario,
>
> There were quite many changes in v5 so I'd prefer the test branch using
> v5.

Done!

https://lore.kernel.org/linux-pci/20261110-superm1-genoa-mess-v1-0-bdcb3a6f2463@xxxxxxxxxx/