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Date:   Mon, 6 Apr 2020 16:20:12 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     David Howells <dhowells@redhat.com>
cc:     Waiman Long <longman@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>, linux-mm@kvack.org,
        keyrings@vger.kernel.org, linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] mm: Add kvfree_sensitive() for freeing sensitive data
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On Mon, 6 Apr 2020, David Howells wrote:

> David Rientjes <rientjes@google.com> wrote:
> 
> > > +static inline void kvfree_sensitive(const void *addr, size_t len)
> > > +{
> > > +	if (addr) {
> > 
> > Shouldn't this be if (unlikely(ZERO_OR_NULL_PTR(addr))?
> 
> You've reversed the logic - it needs a '!' there.
> 

Ah lol, yeah.  Probably just better to do

	if (unlikely(ZERO_OR_NULL_PTR(addr)))
		return;

but I agree that mm.h is likely not the right spot.