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Date:   Fri, 12 Jun 2020 12:21:13 +0200
From:   Krzysztof Kozlowski <krzk@kernel.org>
To:     Wolfram Sang <wsa@kernel.org>
Cc:     Oleksij Rempel <linux@rempel-privat.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] i2c: imx: Fix external abort on early interrupt
Message-ID: <20200612102113.GA26056@pi3>
References: <1591796802-23504-1-git-send-email-krzk@kernel.org>
 <20200612090517.GA3030@ninjato>
 <20200612092941.GA25990@pi3>
 <20200612095604.GA17763@ninjato>
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On Fri, Jun 12, 2020 at 11:56:04AM +0200, Wolfram Sang wrote:
> On Fri, Jun 12, 2020 at 11:29:41AM +0200, Krzysztof Kozlowski wrote:
> > On Fri, Jun 12, 2020 at 11:05:17AM +0200, Wolfram Sang wrote:
> > > On Wed, Jun 10, 2020 at 03:46:42PM +0200, Krzysztof Kozlowski wrote:
> > > > If interrupt comes early (could be triggered with CONFIG_DEBUG_SHIRQ),
> > > 
> > > That code is disabled since 2011 (6d83f94db95c ("genirq: Disable the
> > > SHIRQ_DEBUG call in request_threaded_irq for now"))? So, you had this
> > > without fake injection, I assume?
> > 
> > No, I observed it only after enabling DEBUG_SHIRQ (to a kernel with
> > some debugging options already).
> 
> Interesting. Maybe probe was deferred and you got the extra irq when
> deregistering?

Yes, good catch. The abort happens right after deferred probe exit.  It
could be then different reason than I thought - the interrupt is freed
through devm infrastructure quite late.  At this time, the clock might
be indeed disabled (error path of probe()).

Best regards,
Krzysztof