linux-kernel - Re: [PATCH bpf-next v8 1/3] perf: Add rctx in perf_callchain

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260128085945.GF3372621@noisy.programming.kicks-ass.net>
Date: Wed, 28 Jan 2026 09:59:45 +0100
From: Peter Zijlstra <peterz@...radead.org>
To: Tao Chen <chen.dylane@...ux.dev>
Cc: mingo@...hat.com, acme@...nel.org, namhyung@...nel.org,
	mark.rutland@....com, alexander.shishkin@...ux.intel.com,
	jolsa@...nel.org, irogers@...gle.com, adrian.hunter@...el.com,
	kan.liang@...ux.intel.com, song@...nel.org, ast@...nel.org,
	daniel@...earbox.net, andrii@...nel.org, martin.lau@...ux.dev,
	eddyz87@...il.com, yonghong.song@...ux.dev,
	john.fastabend@...il.com, kpsingh@...nel.org, sdf@...ichev.me,
	haoluo@...gle.com, linux-perf-users@...r.kernel.org,
	linux-kernel@...r.kernel.org, bpf@...r.kernel.org
Subject: Re: [PATCH bpf-next v8 1/3] perf: Add rctx in perf_callchain_entry

On Mon, Jan 26, 2026 at 03:43:29PM +0800, Tao Chen wrote:
> Record rctx inside the perf_callchain_entry itself, when callers of
> get_callchain_entry no longer care about the assignment of rctx, and
> will be used in the next patch.

Sorry, what?

The recursion context is very much about the caller, and very much not
about the data. This just doesn't make sense.