Messages in this thread | | | Date | Thu, 25 Sep 2014 16:40:35 +0200 | From | Joerg Roedel <> | Subject | Re: [PATCH 0/2] iommu: Fix regression in IOMMU grouping |
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On Fri, Sep 19, 2014 at 10:03:00AM -0600, Alex Williamson wrote: > We've had surprisingly little fallout from the DMA alias changes, but > unfortunately one regression has popped up. We have an AMD system > that seems to use the SATA controller to master transactions for the > legacy IDE controller and they are different slots on the root complex. > The IVRS reports 00:11.0 (SATA) as an alias from 00:14.1 (IDE), which > doesn't work with the new, converged PCI IOMMU grouping code, where > we've made a simplifying assumption that aliases will be to the same > slot. > > To fix this, we need to rip out that assumption and write the alias > search code that I was unable to come up with previously. I think > this can now do the chaining of aliases, which I referenced in the > removed comments. Any sort of multi-level aliases are exceptionally > unlikely, but I think this code can now handle whatever firmware and > alias quirks can throw at it.
Applied to core, thanks Alex.
> > I know this is late for 3.17, but this is a regression from the prior > code. If reviews and testing can give us the confidence to put it in > for 3.17, that would be my preference. I've also marked it for stable > in case we want to loop back through that way. Thanks,
The change is too big to make it into v3.17 at this point of the development cycle, so I queued it up for the upcoming merge window.
Joerg
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