Messages in this thread | | | Date | Tue, 18 Oct 2022 07:13:43 +0100 | Subject | Re: [PATCH v4 05/16] iommu: Move bus setup to IOMMU device registration | From | Jon Hunter <> |
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On 06/10/2022 16:27, Robin Murphy wrote: > On 2022-10-06 15:01, Jon Hunter wrote: >> Hi Robin, >> >> On 15/08/2022 17:20, Robin Murphy wrote: >>> Move the bus setup to iommu_device_register(). This should allow >>> bus_iommu_probe() to be correctly replayed for multiple IOMMU instances, >>> and leaves bus_set_iommu() as a glorified no-op to be cleaned up next. >>> >>> At this point we can also handle cleanup better than just rolling back >>> the most-recently-touched bus upon failure - which may release devices >>> owned by other already-registered instances, and still leave devices on >>> other buses with dangling pointers to the failed instance. Now it's easy >>> to clean up the exact footprint of a given instance, no more, no less. >> >> >> Since this change, I have noticed that the DRM driver on Tegra20 is >> failing to probe and I am seeing ... >> >> tegra-gr2d 54140000.gr2d: failed to attach to domain: -19 >> drm drm: failed to initialize 54140000.gr2d: -19 >> >> Bisect points to this change and reverting it fixes it. Let me know if >> you have any thoughts. > > Oh, apparently what's happened is that I've inadvertently enabled the > tegra-gart driver, since it seems that *wasn't* calling bus_set_iommu() > before. Looking at the history, it appears to have been that way since > c7e3ca515e78 ("iommu/tegra: gart: Do not register with bus"), so > essentially that driver has been broken and useless for close to 8 years > now :( > > Given that, I'd be inclined to "fix" it as below, or just give up and > delete the whole thing. > > Thanks, > Robin. > > ----->8----- > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index 5c5cb5bee8b6..7b3f7fd6e527 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -230,6 +230,7 @@ config TEGRA_IOMMU_GART > bool "Tegra GART IOMMU Support" > depends on ARCH_TEGRA_2x_SOC > depends on TEGRA_MC > + depends on BROKEN > select IOMMU_API > help > Enables support for remapping discontiguous physical memory
Thanks Robin. This works for me.
Thierry, Dmitry, we need a fix for v6.1 and so OK with the above?
Jon
-- nvpublic
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