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Date: Mon, 13 Jul 2026 09:38:36 -1000
Message-ID: <053a03ca896099034d6d583e8d566cc2@kernel.org>
From: Tejun Heo <tj@kernel.org>
To: ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, eddyz87@gmail.com, memxor@gmail.com
Cc: martin.lau@linux.dev, emil@etsalapatis.com, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, bpf@vger.kernel.org, sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCHSET SLOP RFC 6/6] sched_ext: Convert scx_bpf_cid_override() to take an arena pointer
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References: <20260713024414.3759854-1-tj@kernel.org> <20260713024414.3759854-7-tj@kernel.org> <20260713025916.68A941F000E9@smtp.kernel.org>
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On the pre-existing READ_ONCE() note:

Agreed as hardening for concurrently-writable arena memory (in practice c
is a register-held local, so the reload doesn't happen, but READ_ONCE()
is the more robust idiom). This is a NOT_SIGNED_OFF demo; I'll add it in
the sched_ext rework after bpf-next is pulled in, not in this RFC patch.

Thanks.