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

...

• /* 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.