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V" , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo Pieralisi Subject: Re: [PATCH v16 22/45] KVM: arm64: CCA: Handle RMI_EXIT_RIPAS_CHANGE Message-ID: References: <20260803134403.80630-1-steven.price@arm.com> <20260803134403.80630-23-steven.price@arm.com> <86fqzl4biu.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <86fqzl4biu.wl-maz@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260907_041256_327848_929E07A1 X-CRM114-Status: GOOD ( 14.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Marc, On 09/07 11:10, Marc Zyngier wrote: > On Mon, 07 Sep 2026 06:05:29 +0100, > Kohei Enju wrote: > > [...] > > > Although the root cause is an RMM bug, should we also guard RIPAS_SET > > against this no-progress case? > > No. We really should *prevent* the kernel from using a known broken > RMM. I understand. > Which brings me to one of my long standing request: how to we > enforce the minimum version of RMM that KVM is willing to work with? > > We absolutely need to have a hard deprecation mechanism in place > before day-1. Agreed. Such a mechanism is clearly necessary. Is there any ongoing work to address this that you are aware of? This seems like a fairly broad topic that may require a separate discussion. Thanks, Kohei > > M. > > -- > Without deviation from the norm, progress is not possible.