Re: [PATCH] selftests/mm: Fix soft-dirty kselftest supported check

[Andrew Morton <akpm@linux-foundation.org>]

On Tue, 24 Mar 2026 16:23:24 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Mon, 23 Mar 2026 12:56:33 +0100 "David Hildenbrand (Arm)" <david@kernel.org> wrote:
> 
> > > +		supported = __pagemap_scan_get_categories(fd, test_area, &r) >= 0;
> > 
> > You have to cast it to a (long) first before comparing, like we do in
> > pagemap_scan_get_categories().
> > 
> > 
> > Maybe best written as
> > 
> > 	long ret = __pagemap_scan_get_categories(fd, test_area, &r);
> > 
> > 	if (ret >= 0)
> > 		supported = 1;
> > 
> > > +		ksft_print_msg("errno: %d\n", errno);
> > 
> > I guess we should drop that, was mostly for testing.

oops, sorry, just learned the difference between "delete" and "send"

I was going to say "unclear why we're printing the errno from a
successful mmap()".