On Thu 07 Dec 2017 08:16:41 PM CET, Eric Blake wrote: >> qemu_io('-f', iotests.imgfmt, >> - '-c', 'write -P %d %d %d' % (i, i*1024*1024, num_kb * >> 1024), >> + '-c', 'write -P 0xFF %dk %dk' % (i * 512, num_kb), > > I guess changing from a variable to a fixed 0xff pattern doesn't make > a difference?
I noticed that with the previous code we would write zeroes to the first image (i == 0), and with that I can't reproduce the bug. I assume that block-stream doesn't copy the data in that case. Changing it to anything != 0 solves the problem. And answering your question, it doesn't really matter if we write the same value in all places, we only check the output of 'qemu-io -c map'. Plus the areas don't even overlap. Berto