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Date:   Thu, 26 May 2022 12:15:36 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Vincent Donnefort <vdonnefort@google.com>
Cc:     tglx@linutronix.de, linux-kernel@vger.kernel.org,
        vschneid@redhat.com, kernel-team@android.com,
        Derek Dolney <z23@posteo.net>
Subject: Re: [PATCH v2] cpu/hotplug: Do not bail-out in DYING/STARTING
 sections
Message-ID: <20220526101536.GP2578@worktop.programming.kicks-ass.net>
References: <20220523160536.2889162-1-vdonnefort@google.com>
 <20220525165248.GI2578@worktop.programming.kicks-ass.net>
 <Yo85PLANCnCcMgvD@google.com>
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On Thu, May 26, 2022 at 09:24:28AM +0100, Vincent Donnefort wrote:
> On Wed, May 25, 2022 at 06:52:48PM +0200, Peter Zijlstra wrote:
> > On Mon, May 23, 2022 at 05:05:36PM +0100, Vincent Donnefort wrote:
> > > The DYING/STARTING callbacks are not expected to fail. However, as reported
> > > by Derek, drivers such as tboot are still free to return errors within
> > > those sections. In that case, there's nothing the hotplug machinery can do,
> > > so let's just proceed and log the failures.
> > > 
> > 
> > I'm confused. Why isn't this a driver bug?
> 
> It is a entirely a driver bug which has been reported already. but 453e41085183
> (cpu/hotplug: Add cpuhp_invoke_callback_range()) changed the behaviour so I
> thought it would be worth to revert to the original one which is to not break
> the entire up/down for a single driver error.

Ah I see. Fair enough I suppose.