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charset="us-ascii" X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm@vger.kernel.org, David Hildenbrand , linux-mips@vger.kernel.org, linux-mm@kvack.org, Marc Zyngier , linux-trace-kernel@vger.kernel.org, Nicholas Piggin , Bibo Mao , loongarch@lists.linux.dev, Atish Patra , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Thomas Bogendoerfer , linux-kernel@vger.kernel.org, Oliver Upton , linux-perf-users@vger.kernel.org, kvm-riscv@lists.infradead.org, Anup Patel , Paolo Bonzini , Andrew Morton , Tianrui Zhao , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Apr 19, 2024, Will Deacon wrote: > > @@ -663,10 +669,22 @@ static __always_inline kvm_mn_ret_t __kvm_handle_hva_range(struct kvm *kvm, > > break; > > } > > r.ret |= range->handler(kvm, &gfn_range); > > + > > + /* > > + * Use a precise gfn-based TLB flush when possible, as > > + * most mmu_notifier events affect a small-ish range. > > + * Fall back to a full TLB flush if the gfn-based flush > > + * fails, and don't bother trying the gfn-based flush > > + * if a full flush is already pending. > > + */ > > + if (range->flush_on_ret && !need_flush && r.ret && > > + kvm_arch_flush_remote_tlbs_range(kvm, gfn_range.start, > > + gfn_range.end - gfn_range.start + 1)) > > What's that '+ 1' needed for here? (a) To see if you're paying attention. (b) Because more is always better. (c) Because math is hard. (d) Because I haven't tested this. (e) Both (c) and (d).