[PATCH 0/2] x86/mm/pkeys: fix user-visible pkey state destruction at fork()

Hi x86 maintainers,

This is an important fix that I believe needs to be merged for 4.21. Without it, applications calling fork() can potentially double-allocate a protection key, causing lots of strange problems.

Thomas's Reviewed-by is on the the actual fix, but not the selftest.

I would also be happy to send this as a pull request if you would prefer.

Cc: x86@kernel.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: Borislav Petkov bp@alien8.de Cc: "H. Peter Anvin" hpa@zytor.com Cc: Peter Zijlstra peterz@infradead.org Cc: Michael Ellerman mpe@ellerman.id.au Cc: Will Deacon will.deacon@arm.com Cc: Andy Lutomirski luto@kernel.org Cc: Joerg Roedel jroedel@suse.de Cc: stable@vger.kernel.org