On 10/10/22 03:58, Clément Léger wrote: > Le Fri, 7 Oct 2022 15:45:17 -0700, > Sonal Santan <sonal.santan@xxxxxxx> a écrit : > >>>> Bringing this thread back into focus. Any thoughts on how to move forward? >>> >>> Reviewers raise concerns/issues and the submitters work to address >>> them or explain why they aren't an issue. The submitter has to push >>> things forward. That's how the process works. >>> > > Up to now, there does not seems to be a better solution to this > problem in term of maintainability, reusability and ease of use. > > Again, patching the pre-boot description (ACPI or DT) is not an option, > the user is entitled to plug the card in whatever PCI slot he wants. > This is either probbly not possible and ACPI based system and would > require a difficult setup to even try to achieve that. This would also > result in two different description to support the same device. > >> We are working on updating the patch set to address the feedback. The >> design is still based on device tree overlay infrastructure. > > Agreed, moreover saying that "the overlay support is fragile" seems to > be a shortcut to do nothing and move all the support outside of the > kernel. If buggy, then it would be better to fix this support (if there > are real problems encountered with it) or kill it by removing it > entirely if not usable (option 1 would of course be preferred). "Buggy" is true, but not an adequate description. See my other reply in this thread a couple of minutes ago regarding "proof of concept". Rob has suggested removing it at least a couple of times this year. -Frank > >> >>> As I noted, much of this is needed on a DT system with PCI device not >>> described in DT. So you could split out any ACPI system support to >>> avoid that concern for example. Enabling others to exercise these >>> patches may help too. Perhaps use QEMU to create some imaginary >>> device. >> To verify this patch set, in addition to a x86_64/ACPI based system, we >> also have an AARCH64/DT QEMU setup where we have attached a physical >> Alveo device. We haven't run into any ACPI or DTO issues so far. > > I've been able to use the same patch set with a X86 QEMU system by > attaching my physical PCI card to it. No issues were encountered > (although the usage was rather limited). Gaining some users of this > support would allow to gather more feedback. > >> >> Perhaps we can introduce this feature in a phased manner where we first >> enable DT based platforms and then enable ACPI based platforms? >> >> -Sonal >>> >>> Rob > >
