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>> + if (!cxled && cxld->interleave_ways > 8) { > > Why does this check make sense now when we didn't have it before > (that I can find anyway)? If it isn't tightly coupled to this > patch and instead is providing some extra checks that are worthwhile > I'd break it out as a separate patch where that usecase can be > well described. > I dropped the new > 8 check from v14 patch 7. It was not present in the original code, and this patch is intended to only share the existing unpacking behavior. >> + >> + if (!committed) >> + size = 0; >> + if (base == U64_MAX || size == U64_MAX || >> + (size && base > U64_MAX - (size - 1))) >> + return -ENXIO; > > This second block looks like new defences which is fine but I'm not sure > it makes sense in here. Also given we are just checking overflow > doesn't happen maybe use check_add_overflow(). Saves us thinking too > much the maths. > Agreed. V14 puts the overflow check in a separate patch, 8/16, and uses check_add_overflow(). >> + >> + hpa_range = (struct range) { >> + .start = base, >> + .end = base + size - 1, >> + }; >> + target_type = FIELD_GET(CXL_HDM_DECODER0_CTRL_HOSTONLY, ctrl) ? >> + CXL_DECODER_HOSTONLYMEM : CXL_DECODER_DEVMEM; > > Maybe stick to the if / else of the original? I think that is more readable for > an extra couple of lines. > Also blank line here to give visual separation before the conditional that > follows. Ack. V14 keeps the original if/else. > > It's a functional change to move the target_type selection out of the > committed check. I'd like to see some discussion of why that is fine to > do which probably means a separate little patch that has that description > on its own. Ack. V14 selects the target type only when the decoder is committed, preserving the existing behavior. -- Regards, Srirangan