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From:   Vladimir Oltean <vladimir.oltean@nxp.com>
To:     Pavel Skripkin <paskripkin@gmail.com>
CC:     Claudiu Manoil <claudiu.manoil@nxp.com>,
        "alexandre.belloni@bootlin.com" <alexandre.belloni@bootlin.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrew Lunn <andrew@lunn.ch>
Subject: Re: [PATCH v4] net: ocelot: fix wrong time_after usage
Thread-Topic: [PATCH v4] net: ocelot: fix wrong time_after usage
Thread-Index: AQHYkTxWR3oKNEKHnk6aIqZkbKC6CK1xVrOA
Date:   Wed, 6 Jul 2022 13:30:42 +0000
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References: <20220706132845.27968-1-paskripkin@gmail.com>
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On Wed, Jul 06, 2022 at 04:28:45PM +0300, Pavel Skripkin wrote:
> Accidentally noticed, that this driver is the only user of
> while (time_after(jiffies...)).
>=20
> It looks like typo, because likely this while loop will finish after 1st
> iteration, because time_after() returns true when 1st argument _is after_
> 2nd one.
>=20
> There is one possible problem with this poll loop: the scheduler could pu=
t
> the thread to sleep, and it does not get woken up for
> OCELOT_FDMA_CH_SAFE_TIMEOUT_US. During that time, the hardware has done
> its thing, but you exit the while loop and return -ETIMEDOUT.
>=20
> Fix it by using sane poll API that avoids all problems described above
>=20
> Fixes: 753a026cfec1 ("net: ocelot: add FDMA support")
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>

This patch should target the "net" tree.=