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: <D98FE55B-C379-4C24-B4DD-4E02A1E2AB79@joelfernandes.org>
Date:   Tue, 29 Aug 2023 06:12:35 -0400
From:   Joel Fernandes <joel@...lfernandes.org>
To:     Frederic Weisbecker <frederic@...nel.org>
Cc:     "Paul E. McKenney" <paulmck@...nel.org>,
        Z qiang <qiang.zhang1211@...il.com>,
        linux-kernel@...r.kernel.org, rcu@...r.kernel.org
Subject: Re: [PATCH] rcutorture: Traverse possible cpu to set maxcpu in rcu_nocb_toggle()



> On Aug 29, 2023, at 5:24 AM, Frederic Weisbecker <frederic@...nel.org> wrote:
> 
> On Mon, Aug 28, 2023 at 05:51:09PM -0400, Joel Fernandes wrote:
>> I think the issue is the loop later in the function does
>> not try to toggle cpus that came online too late.
>> 
>> So it does not test offloading on all CPUs just because max got updated too
>> late.
> 
> Right, and therefore for_each_possible_cpu() or for_each_present_cpu()
> should be fine to iterate since it's ok to try to toggle an offline CPU.

Ah I see what you mean, sounds good.

> 
>> 
>> One fix could be to periodically check in the loop if a new cpu at maxcpu + 1
>> ever got onlined. If it did, update the maxcpu.
> 
> Is it worth the complication though?

Probably not and so your suggestion sounds fine.

Thanks!

 - Joel


> 
> Thanks.
> 
>> 
>> Thanks.
>> 
>> 
>>> 
>>> Thanks.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ