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Peter Anvin" , "Paul E . McKenney" , Andrey Konovalov , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Catalin Marinas , Christoph Lameter , Dave Hansen , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Hillf Danton , Ingo Molnar , Jonathan.Cameron@huawei.com, Jonathan Corbet , Joonsoo Kim , Kees Cook , Mark Rutland , Pekka Enberg , Peter Zijlstra , sjpark@amazon.com, Thomas Gleixner , Vlastimil Babka , Will Deacon , "the arch/x86 maintainers" , linux-doc@vger.kernel.org, kernel list , kasan-dev , Linux ARM , Linux-MM Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 29, 2020 at 3:38 PM Marco Elver wrote: > Add architecture specific implementation details for KFENCE and enable > KFENCE for the x86 architecture. In particular, this implements the > required interface in for setting up the pool and > providing helper functions for protecting and unprotecting pages. [...] > diff --git a/arch/x86/include/asm/kfence.h b/arch/x86/include/asm/kfence.h [...] > +/* Protect the given page and flush TLBs. */ > +static inline bool kfence_protect_page(unsigned long addr, bool protect) > +{ [...] > + flush_tlb_one_kernel(addr); flush_tlb_one_kernel() -> flush_tlb_one_user() -> __flush_tlb_one_user() -> native_flush_tlb_one_user() only flushes on the local CPU core, not on others. If you want to leave it this way, I think this needs a comment explaining why we're not doing a global flush (locking context / performance overhead / ... ?).