Re: [PATCH v1 1/7] selftests/vm: anon_cow: test COW handling of anonymous memory

[David Hildenbrand]

> > +	/* See if we still read the old values via the pipe. */
> > +	for (total = 0; total < transferred; total += cur) {
> > +		cur = read(fds[0], new + total, transferred - total);
> > +		if (cur < 0)
>
> Hi David,
> I was looking at some coccinelle reports for linux-next and
> saw the following warning for this comparison:
>
>    WARNING: Unsigned expression compared with zero: cur < 0
>
> I think 'cur' needs to be of type 'ssize_t' for this comparison to work.
>
> The same warning is reported for the variable 'transferred' above, and
> also for do_test_iouring() and do_test_vmsplice_in_parent() in
> "selftests/vm: anon_cow: add liburing test cases".

Thanks for reporting! Indeed, we need a signed value.

--
Thanks,

David / dhildenb