Messages in this thread | | | Date | Mon, 21 Mar 2022 09:43:46 -0300 | From | Jason Gunthorpe <> | Subject | Re: [PATCH RFC 10/11] iommu: Make IOPF handling framework generic |
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On Mon, Mar 21, 2022 at 11:42:16AM +0000, Jean-Philippe Brucker wrote:
> I tend to disagree with that last part. The fault is caused by a specific > device accessing shared page tables. We should keep that device > information throughout the fault handling, so that we can report it to the > driver when things go wrong.
SVA faults should never be reported to drivers??
> A process can have multiple threads bound to different devices, they > share the same mm so if the driver wanted to signal a misbehaving > thread, similarly to a SEGV on the CPU side, it would need the > device information to precisely report it to userspace.
I'm not sure I understand this - we can't match DMAs to executing CPUs. On fault we fail the DMA and let the process keep running or SIGSEGV the whole thread group.
Jason
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