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@xxxxxxxxxx Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Joerg Roedel <jroedel@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx
