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    SubjectRe: [PATCH 5.19 0191/1157] hwmon: (sht15) Fix wrong assumptions in device remove callback
    Hello,

    On Mon, Aug 15, 2022 at 07:52:27PM +0200, Greg Kroah-Hartman wrote:
    > From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
    >
    > [ Upstream commit 7d4edccc9bbfe1dcdff641343f7b0c6763fbe774 ]
    >
    > Taking a lock at the beginning of .remove() doesn't prevent new readers.
    > With the existing approach it can happen, that a read occurs just when
    > the lock was taken blocking the reader until the lock is released at the
    > end of the remove callback which then accessed *data that is already
    > freed then.
    >
    > To actually fix this problem the hwmon core needs some adaption. Until
    > this is implemented take the optimistic approach of assuming that all
    > readers are gone after hwmon_device_unregister() and
    > sysfs_remove_group() as most other drivers do. (And once the core
    > implements that, taking the lock would deadlock.)
    >
    > So drop the lock, move the reset to after device unregistration to keep
    > the device in a workable state until it's deregistered. Also add a error
    > message in case the reset fails and return 0 anyhow. (Returning an error
    > code, doesn't stop the platform device unregistration and only results
    > in a little helpful error message before the devm cleanup handlers are
    > called.)
    >
    > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
    > Link: https://lore.kernel.org/r/20220725194344.150098-1-u.kleine-koenig@pengutronix.de
    > Signed-off-by: Guenter Roeck <linux@roeck-us.net>
    > Signed-off-by: Sasha Levin <sashal@kernel.org>

    Does this mean my concerns I expressed in the mail with Message-Id:
    20220814155638.idxnihylofsxqlql@pengutronix.de were not taken into
    consideration?

    Best regards
    Uwe

    --
    Pengutronix e.K. | Uwe Kleine-König |
    Industrial Linux Solutions | https://www.pengutronix.de/ |
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