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([49.142.96.162]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-23de4345e6bsm81331175ad.192.2025.07.13.19.14.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 13 Jul 2025 19:14:08 -0700 (PDT) From: DaeRo Lee X-Google-Original-From: DaeRo Lee To: will@kernel.org Cc: alexandru.elisei@arm.com, james.morse@arm.com, kernel-team@android.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, maz@kernel.org, oliver.upton@linux.dev, qperret@google.com, sebastianene@google.com, skseofh@gmail.com, sudeep.holla@arm.com, suzuki.poulose@arm.com, tabba@google.com Subject: Re: [PATCH v3 08/10] KVM: arm64: Handle FFA_MEM_LEND calls from the host Date: Mon, 14 Jul 2025 11:14:00 +0900 Message-Id: <20250714021400.631762-1-skseofh@naver.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250713_191410_127506_FCCDB866 X-CRM114-Status: UNSURE ( 6.89 ) X-CRM114-Notice: Please train this message. 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 Is it pKVM's policy to not manage Non-secure memory using FF-A, while the FF-A specification supports memory management between Host/Guest within Non-secure hypervisors? Then, how does someone lend memory to a Guest from the Host/Guest via FF-A? Can pKVM prevent this? Or should Host/Guest developers use it with caution?