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Seeing your reply on IRC, here an attempt at a release justification (the patches were ready by Oct 29, but no-one cared to commit them in my absence, so I thought I'd get away without such a write-up): Patch 1 addresses a regression identified by Andrew. The main risk I see here (which has turned up only very recently) is disagreement on patch 3 which imo has an effect also on what patch 1 does, as to the (non-)effects of "iommu=off" on the hypervisor command line. This, however, is not an effect of the patch, but pre-existing behavior. The behavioral change (in this regard) is in patch 3, which is still under discussion. Patch 2 corrects an (unlikely but not impossible to be taken) error path, supposedly making systems functional again in case they would in fact cause that error path to be taken. The risk looks low to me, given that two function calls with previously assumed to be identical results now get folded into one with the result latched. Jan > Andrew, did you perhaps have a chance to actually try v2 of patch 1? It > works for me when suitably configuring the BIOS on my Skylake, so I > wouldn't feel uncertain in committing without a Tested-by, but it would > feel even better if I had one. > > Thanks, Jan >