Am 20.05.2010 08:09, schrieb Avi Kivity: > On 05/20/2010 12:09 AM, Kevin Wolf wrote: >> >>> Actually it's not that obvious. If the actual problem >>> here (besides the mis-comparison) is due to missing >>> barriers or flushes. Avi asked a good question in that >>> thread. >>> >> It's obvious that it's a hack. It doesn't fix anything, it just disables a >> feature that didn't work. Good for debugging, but not something that you >> would like to commit. >> >> It's reasonable to include something like this when we know that something is >> broken but we haven't found it yet - but I believe Christoph's patch is the >> real fix. If anyone can still find a case that is "fixed" by Avi's patch, I >> could be convinced to apply it anyway, but I'd prefer if I didn't have to. >> >> Note that we actually don't have overlapping requests. It just looks like it >> because the qsort call doesn't work correctly with the broken comparison >> function, so lower sector numbers can come after higher ones. >> > > I agree my patch didn't fix the problem, only made it disappear, but > won't the current code break with overlapping requests?
Maybe --verbose for your patch descriptions would help. I didn't see any obvious problem. If you know any, care to explain? Anyway, I started to implement a multiwrite command for qemu-io yesterday, so that I can actually test such scenarios. Kevin
