Hi, Cristoph.
Another DMA related question before I start to post patches in this area
again..
Our virtual SCSI device (which BTW is fully DMA compliant) has a large
queue depth and therefore runs out of SWIOTLB space => The scsi middle
layer behaves nicely and asks the driver to retry the dma mapping
operation. All fine.
The problem is that while this happens, the kernel log spits out a
number of dma- and SWIOTLB errors, which are really harmless.
While one could probably just say go and increase the SWIOTLB size, but
on some systems that might not be doable.
We could reduce the queue depth when SEV is active, which is probably
one of those hacky solutions you dislike.
We could silence the dma- and swiotlb errors? At least selectively for
some devices?
Do you have any guidance into the best solution here?
Thanks,
Thomas.
