linux-kernel - Re: [PATCH v3 33/57] perf: Simplify perf_adjust_freq_unthr

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]

Date:   Mon, 12 Jun 2023 22:05:25 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Linus Torvalds <torvalds@...ux-foundation.org>
Cc:     keescook@...omium.org, gregkh@...uxfoundation.org,
        pbonzini@...hat.com, masahiroy@...nel.org, nathan@...nel.org,
        ndesaulniers@...gle.com, nicolas@...sle.eu,
        catalin.marinas@....com, will@...nel.org, vkoul@...nel.org,
        trix@...hat.com, ojeda@...nel.org, mingo@...hat.com,
        longman@...hat.com, boqun.feng@...il.com, dennis@...nel.org,
        tj@...nel.org, cl@...ux.com, acme@...nel.org, mark.rutland@....com,
        alexander.shishkin@...ux.intel.com, jolsa@...nel.org,
        namhyung@...nel.org, irogers@...gle.com, adrian.hunter@...el.com,
        juri.lelli@...hat.com, vincent.guittot@...aro.org,
        dietmar.eggemann@....com, rostedt@...dmis.org, bsegall@...gle.com,
        mgorman@...e.de, bristot@...hat.com, vschneid@...hat.com,
        paulmck@...nel.org, frederic@...nel.org, quic_neeraju@...cinc.com,
        joel@...lfernandes.org, josh@...htriplett.org,
        mathieu.desnoyers@...icios.com, jiangshanlai@...il.com,
        rientjes@...gle.com, vbabka@...e.cz, roman.gushchin@...ux.dev,
        42.hyeyoo@...il.com, apw@...onical.com, joe@...ches.com,
        dwaipayanray1@...il.com, lukas.bulwahn@...il.com,
        john.johansen@...onical.com, paul@...l-moore.com,
        jmorris@...ei.org, serge@...lyn.com, linux-kbuild@...r.kernel.org,
        linux-kernel@...r.kernel.org, dmaengine@...r.kernel.org,
        llvm@...ts.linux.dev, linux-perf-users@...r.kernel.org,
        rcu@...r.kernel.org, linux-security-module@...r.kernel.org,
        tglx@...utronix.de, ravi.bangoria@....com, error27@...il.com,
        luc.vanoostenryck@...il.com
Subject: Re: [PATCH v3 33/57] perf: Simplify perf_adjust_freq_unthr_context()

On Mon, Jun 12, 2023 at 11:55:57AM -0700, Linus Torvalds wrote:

> So while it might not be the horrible bug I thought it was, I'd
> _really_ like us to not do those things just from a sanity angle.

OK, let me go see if there's another way to sanely write those.


Is this less offensive?

restart:
	scoped_guard (rcu) {
		list_for_each_entry_rcu(..) {
			...
			if (err == -EAGAIN)
				goto restart;
		}
	}


That has the explicit scope on the rcu and now the goto explicitly exist
it.

Gonna have to think what to do about the continue ...