20065ae005
[ Upstream commit e5b499f6fb17bc95a813e85d0796522280203806 ] We must free/disable all interrupts and cancel all pending works before doing further cleanup. Before this commit arizona_extcon_remove() was doing several register writes to shut things down before disabling the IRQs and it was cancelling only 1 of the 3 different works used. Move all the register-writes shutting things down to after the disabling of the IRQs and add the 2 missing cancel_delayed_work_sync() calls. This fixes various possible races on driver unbind. One of which would always trigger on devices using the mic-clamp feature for jack detection. The ARIZONA_MICD_CLAMP_MODE_MASK update was done before disabling the IRQs, causing: 1. arizona_jackdet() to run 2. detect a jack being inserted (clamp disabled means jack inserted) 3. call arizona_start_mic() which: 3.1 Enables the MICVDD regulator 3.2 takes a pm_runtime_reference And this was all happening after the ARIZONA_MICD_ENA bit clearing, which would undo 3.1 and 3.2 because the ARIZONA_MICD_CLAMP_MODE_MASK update was being done after the ARIZONA_MICD_ENA bit clearing. So this means that arizona_extcon_remove() would exit with 1. MICVDD enabled and 2. The pm_runtime_reference being unbalanced. MICVDD still being enabled caused the following oops when the regulator is released by the devm framework: [ 2850.745757] ------------[ cut here ]------------ [ 2850.745827] WARNING: CPU: 2 PID: 2098 at drivers/regulator/core.c:2123 _regulator_put.part.0+0x19f/0x1b0 [ 2850.745835] Modules linked in: extcon_arizona ... ... [ 2850.746909] Call Trace: [ 2850.746932] regulator_put+0x2d/0x40 [ 2850.746946] release_nodes+0x22a/0x260 [ 2850.746984] __device_release_driver+0x190/0x240 [ 2850.747002] driver_detach+0xd4/0x120 ... [ 2850.747337] ---[ end trace f455dfd7abd9781f ]--- Note this oops is just one of various theoretically possible races caused by the wrong ordering inside arizona_extcon_remove(), this fixes the ordering fixing all possible races, including the reported oops. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com> Tested-by: Charles Keepax <ckeepax@opensource.cirrus.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.