Re: [syzbot] WARNING: refcount bug in sys_memfd_secret

[Matthew Wilcox]

On Sat, Oct 23, 2021 at 10:03:11AM -0700, Kees Cook wrote:
> On October 23, 2021 8:27:28 AM PDT, Mike Rapoport <rppt@xxxxxxxxxx> wrote:
> >and my first reaction was to send a revert the untested commit 110860541f44
> >("mm/secretmem: use refcount_t instead of atomic_t"). 

I think you should.  This isn't a real problem.  And it abuses the
refcount_t interface.  Your hack is clever, but it's fundamentally
wrong.