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Peter Anvin" , "the arch/x86 maintainers" , Linux Kernel Mailing List , linux-mm , Andy Lutomirski , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , "Liguori, Anthony" , Daniel Gruss , Hugh Dickins , Kees Cook , Andrea Arcangeli , Waim@linux.intel.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 18, 2018 at 4:26 PM, Andi Kleen wrote: > > Seems like a hack. Why can't that be stored in a per cpu variable? It *is* a percpu variable - the whole x86_tss structure is percpu. I guess it could be a different (separate) percpu variable, but might as well use the space we already have allocated. Linus