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In-Reply-To: <Y0A97NrHvzkfaG0J@linutronix.de>
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
Date:   Fri, 7 Oct 2022 09:32:40 -0600
Message-ID: <CAHmME9rhtZrwns_d7gQc8vrhWHKZqv6PkWi=JSQXsQOvvRr8UA@mail.gmail.com>
Subject: Re: [PATCH 2/2] random: spread out jitter callback to different CPUs
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     tglx@linutronix.de, linux-kernel@vger.kernel.org,
        linux-crypto@vger.kernel.org,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Sultan Alsawaf <sultan@kerneltoast.com>
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On Fri, Oct 7, 2022 at 8:55 AM Sebastian Andrzej Siewior
<bigeasy@linutronix.de> wrote:
>
> On 2022-10-07 08:01:20 [-0600], Jason A. Donenfeld wrote:
> > Here's a reproducer of this flow, which prints out:
> >
> >     [    4.157610] wireguard: Stack on cpu 1 is corrupt
>
> I understood Sultan's description. The end of story (after discussing
> this tglx) is that this will be documented since it can't be fixed for
> add_timer_on().

Right, that's about where I wound up too, which is why I just
abandoned the approach of this patchset. Calling del_timer_sync()
before each new add_timer_on() (but after !timer_pending()) seems
kinda ugly.

Jason