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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: gysx1ghydyjwuewaswfbtd4p4nw9inh4 X-Rspamd-Queue-Id: 8352E1C0023 X-HE-Tag: 1674673361-820605 X-HE-Meta: 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 wobHzcez jHcCPpHJQBs4cFLkRnhCGqfsNvaFWbc8Zeo67y31QETjx+icKolK3ccYEOP0GBmNJbY2EDYASCqvrKYin59U7WycwTQBTkxDhvV6RwGdQ+/fN8T9VfewhgTnkVZuX+tsb4SGhXoOxbGUsW2DNvR9cwY0lCT26lO7PbbYil4Y9dUByI03WGT36pI7lIw7D2m50Tux0ST5zAGp9moieojJhhcag3FFalM2c9FJWnyJmxoOSe74+T0i+KHBMVU+XbuFC/zg6BDG6r6hGpp7kmBNPmF+OYT11bSbQdYtlljGq7DFYL6Hr1PcPTA28nA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hello, I'm investigating if there is a need to backport x86/pkeys fix/feature into earlier kernel versions, Chrome is starting to use PKEY in x86, and I hope experts here can give advice on this. For background, ChromeOS regularly syncs with upstream kernel versions, and has production that uses 4.4/4.14/4.19/5.4/5.10/5.15. We plan to use PKEY as Stephen R=C3=B6ttger proposed in https://docs.google.com/document/d/1O2jwK4dxI3nRcOJuPYkonhTkNQfbmwdvxQMyXge= aRHo/edit?usp=3Dsharing In short, Chrome will use PKEY to protect a thread and have exclusive access to some pages. If there are fixes/features to make this happen, we can backport those from the ChromeOS branch. Thanks! Best regards, Jeff