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From: Zayd Qumsieh <zayd_qumsieh@apple.com>
To: Hector Martin <marcan@marcan.st>, Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>, Marc Zyngier <maz@kernel.org>,
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 Asahi Linux <asahi@lists.linux.dev>
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>
In-reply-to: Hector Martin <f6484dcd-ebf6-4b6f-be17-69b05539e33b@marcan.st>
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Reply-to: Zayd Qumsieh <zayd_qumsieh@apple.com>
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>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