On Mon 11 Jan 2016 06:42:38 AM CET, Fam Zheng <f...@redhat.com> wrote:
> The implicit casting from unsigned int to double changes negative > values into large positive numbers, whereas explicitly casting to > signed integer first will let us catch the invalid value and report > error correctly: > > $ qemu-system-x86_64 -drive file=null-co://,iops=-1 > qemu-system-x86_64: -drive file=null-co://,iops=-1: bps/iops/maxs > values must be 0 or greater > > throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg = > - qemu_opt_get_number(opts, "throttling.bps-total", 0); > + (int64_t)qemu_opt_get_number(opts, "throttling.bps-total", 0); It seems to me that the problem is that qemu_opt_get_number() returns a value different from the one specified in the comand-line. How do we even tell the difference between a negative number and its bit-to-bit positive equivalent? If we are going to reject very large numbers I would rather check that the throtting values are within a sane range and throw an error otherwise. Berto
