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charset=utf-8 Content-Transfer-Encoding: quoted-printable 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, linux-kernel@vger.kernel.org, David Matlack , linux-riscv@lists.infradead.org, Claudio Imbrenda , Janosch Frank , Marc Zyngier , Huacai Chen , Christian Borntraeger , Albert Ou , Bibo Mao , loongarch@lists.linux.dev, Paul Walmsley , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, Oliver Upton , Palmer Dabbelt , David Stevens , kvm-riscv@lists.infradead.org, Anup Patel , Paolo Bonzini , Tianrui Zhao , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Sean Christopherson writes: > On Thu, Aug 08, 2024, Alex Benn=C3=A9e wrote: >> Sean Christopherson writes: >>=20 >> > Now that hva_to_pfn() no longer supports being called in atomic contex= t, >> > move the might_sleep() annotation from hva_to_pfn_slow() to >> > hva_to_pfn(). >>=20 >> The commentary for hva_to_pfn_fast disagrees. >>=20 >> /* >> * The fast path to get the writable pfn which will be stored in @pfn, >> * true indicates success, otherwise false is returned. It's also the >> * only part that runs if we can in atomic context. >> */ >> static bool hva_to_pfn_fast(struct kvm_follow_pfn *kfp, kvm_pfn_t *pfn) >>=20 >> At which point did it loose the ability to run in the atomic context? I >> couldn't work it out from the commits. > > It didn't lose the ability per se (calling hva_to_pfn_fast() in atomic co= ntext > would still be functionally ok), rather the previous patch > > KVM: Drop @atomic param from gfn=3D>pfn and hva=3D>pfn APIs > > removed support for doing so in order to simplify hva_to_pfn() as a whole. It still sticks out given the only caller no longer enforces this.=20 How about: * true indicates success, otherwise false is returned. It's also the * only part that could run in an atomic context if we wanted to * (although no callers expect it to). ? --=20 Alex Benn=C3=A9e Virtualisation Tech Lead @ Linaro