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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org >I'm probably going to make myself hugely unpopular here, but I have a >strong objection to this patch series as it stands. I firmly believe >that providing a prctl() to query and toggle the memory model to/from >TSO is going to lead to subtle fragmentation of arm64 Linux userspace. It's definitely not our intent to fragment the ecosystem. The goal of this memory ordering is to simplify emulation layers that benefit from this. If you have suggestions to reduce the risk of it being misused outside of emulators, we'd be happy to look into it. Thanks, Zayd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from rn-mailsvcp-mx-lapp02.apple.com (rn-mailsvcp-mx-lapp02.apple.com [17.179.253.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 750421946F for ; Tue, 16 Apr 2024 03:23:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.179.253.23 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713237788; cv=none; b=n1l9mhZ/VJsB+UHUPgZdXWFEeKVZCK3iWancAQgHrKSWbOWhZhU04FBtzYALrrTQc8Spfvqno03c9L6UygznpEXlkBwTsGbD53V2kVVf69Ud3FdCyvp2x4STfc8326P/hj8HhbueO3/qGg5sC4LEHF44A/pabenE7/Oa0Fitqo0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713237788; c=relaxed/simple; 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Mon, 15 Apr 2024 19:22:56 -0700 (PDT) From: Zayd Qumsieh To: Hector Martin , Will Deacon Cc: Catalin Marinas , Marc Zyngier , Mark Rutland , Zayd Qumsieh , Justin Lu , Ryan Houdek , Mark Brown , Ard Biesheuvel , Mateusz Guzik , Anshuman Khandual , Oliver Upton , Miguel Luis , Joey Gouly , Christoph Paasch , Kees Cook , Sami Tolvanen , Baoquan He , Joel Granados , Dawei Li , Andrew Morton , Florent Revest , David Hildenbrand , Stefan Roesch , Andy Chiu , Josh Triplett , Oleg Nesterov , Helge Deller , Zev Weiss , Ondrej Mosnacek , Miguel Ojeda , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Asahi Linux Subject: Re: [PATCH 0/4] arm64: Support the TSO memory model Date: Mon, 15 Apr 2024 19:22:41 -0700 Message-id: <20240416022242.89623-1-zayd_qumsieh@apple.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-reply-to: Hector Martin References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-version: 1.0 Reply-to: Zayd Qumsieh Content-transfer-encoding: 8bit >I'm probably going to make myself hugely unpopular here, but I have a >strong objection to this patch series as it stands. I firmly believe >that providing a prctl() to query and toggle the memory model to/from >TSO is going to lead to subtle fragmentation of arm64 Linux userspace. It's definitely not our intent to fragment the ecosystem. The goal of this memory ordering is to simplify emulation layers that benefit from this. If you have suggestions to reduce the risk of it being misused outside of emulators, we'd be happy to look into it. Thanks, Zayd