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[34.140.183.197]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4a21555f9e1sm10347795e9.4.2026.10.23.01.01.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Oct 2026 01:01:51 -0700 (PDT) Date: Fri, 23 Oct 2026 09:01:42 +0100 From: Vincent Donnefort To: Fuad Tabba Cc: maz@kernel.org, oupton@kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, kernel-team@android.com, tabba@google.com Subject: Re: [PATCH v2 4/4] KVM: arm64: pkvm: Avoid trapping on HVC_RESET_VECTORS Message-ID: References: <20261022140048.2522787-1-vdonnefort@google.com> <20261022140048.2522787-5-vdonnefort@google.com> <20261022173806.3752938-1-fuad.tabba@linux.dev> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261022173806.3752938-1-fuad.tabba@linux.dev> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261023_010154_966426_07B69514 X-CRM114-Status: GOOD ( 13.34 ) X-Spam-Score: -17.6 (-----------------) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIMWL_WL_MED,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Oct 22, 2026 at 06:38:06PM +0100, Fuad Tabba wrote: > Hi Vincent, > > On Thu, 22 Oct 2026 15:00:48 +0100, Vincent Donnefort wrote: > > pKVM prevents the reset of the hypervisor vector and as a consequence, > > kvm_hyp_initialized can never be reset. Add a fast-path for this case to > > skip unnecessary HVCs on the CPU hotplug and PM path. > > Could you drop this patch? It brings back a pKVM check in the host code, > which Marc asked to avoid on v1 [1], to save one HVC that pKVM already > rejects. > > Cheers, > /fuad > > [1] https://lore.kernel.org/all/86jynbyshv.wl-maz@kernel.org/ Exactly why I kept this patch separated :) It is a single documented fast-path while the series removed 5. But I agree this is only for the CPU resume or going out of idle path so not really a hot path. -- Vincent