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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: cm9qxokafkk9f4h4n193bea65o998x84 X-Rspamd-Queue-Id: C52DC16000A X-HE-Tag: 1675765777-686394 X-HE-Meta: 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 3nS6841D gorwPO5QejRPtdsOVeGdIvvDab4eRhDtbUh5g6mCSiCZmPvXxmS2CEeQ6eBEs04CMiPmGnRK9XWo1VfcXdMZ+0f6eIq2Z8nRWMERBl0vk7aVPj8thKKA9Te8E2x6czNM3+JKo4il7bjb6SExXobjRbzyFExg/3DAy2+QZgs8wfbQldtmS7yjnzPCJHz/puRB2KYhr953vUcQjvDDbovsibD9+ItO9e/BbnitO5lGy4esHQIBW6C/NdjwlSCxIYKgXXfgkTJI6SMPvE0U9WegGK52nbghSIYwyVUeL05KWSxqw657LrbCfUWB6Hg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000015, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > > > > What is the problem you have encountered? Is the page-granular direct > > map causing issues? > We're working on a low memory target, page-granular mapping costed more > (2M per 1GB) memory. Due to GKI constraints, it is not easy to disable > CONFIG_KFENCE. So my intention was to move the judgement to runtime > configurable w/ CONFIG_KFENCE on... > > Do you have any further suggestion/proposal on this? Many Thanks! Right now CONFIG_KFENCE allocates 512Kb for the GKI kernel (only 63 objects instead of the default 255): https://cs.android.com/android/kernel/superproject/+/common-android-mainline:common/arch/arm64/configs/gki_defconfig;l=686?q=CONFIG_KFENCE_NUM_OBJECTS Where do 2M come from?