[PATCH v6 00/12] Fix broken usage of driver_override (and kfree of static memory)

From: Krzysztof Kozlowski
Date: Sun Apr 03 2022 - 14:38:22 EST


Hi,

This is a continuation of my old patchset from 2019. [1]
Back then, few drivers set driver_override wrong. I fixed Exynos
in a different way after discussions. QCOM NGD was not fixed
and a new user appeared - IMX SCU.

It seems "char *" in driver_override looks too consty, so we
tend to make a mistake of storing there string literals.

Changes since latest v6
=======================
1. Patch #1: Don't check for !dev and handle len==0 (Andy).
2. New patch #11 (rpmsg): split constifying of local variable to a new patch.

Changes since latest v5
=======================
1. Patch 11 (rpmsg): split from previous patch 11 - easier to understand the
need of it.
2. Fix build issue in patch 12 (rpmsg).

Changes since latest v4
=======================
1. Correct commit msgs and comments after Andy's review.
2. Re-order code in new helper (patch #1) (Andy).
3. Add tags.

Changes since latest v3
=======================
1. Wrap comments, extend comment in driver_set_override() about newline.
2. Minor commit msg fixes.
3. Add tags.

Changes since latest v2
=======================
1. Make all driver_override fields as "const char *", just like SPI
and VDPA. (Mark)
2. Move "count" check to the new helper and add "count" argument. (Michael)
3. Fix typos in docs, patch subject. Extend doc. (Michael, Bjorn)
4. Compare pointers to reduce number of string readings in the helper.
5. Fix clk-imx return value.

Changes since latest v1 (not the old 2019 solution):
====================================================
https://lore.kernel.org/all/708eabb1-7b35-d525-d4c3-451d4a3de84f@xxxxxxxxxxxxxxxxxx/
1. Add helper for setting driver_override.
2. Use the helper.

Dependencies (and stable):
==========================
1. All patches, including last three fixes, depend on the first patch
introducing the helper.
2. The last three commits - fixes - are probably not backportable
directly, because of this dependency. I don't know how to express
this dependency here, since stable-kernel-rules.rst mentions only commits as
possible dependencies.

[1] https://lore.kernel.org/all/1550484960-2392-3-git-send-email-krzk@xxxxxxxxxx/

Best regards,
Krzysztof

Krzysztof Kozlowski (12):
driver: platform: Add helper for safer setting of driver_override
amba: Use driver_set_override() instead of open-coding
fsl-mc: Use driver_set_override() instead of open-coding
hv: Use driver_set_override() instead of open-coding
PCI: Use driver_set_override() instead of open-coding
s390/cio: Use driver_set_override() instead of open-coding
spi: Use helper for safer setting of driver_override
vdpa: Use helper for safer setting of driver_override
clk: imx: scu: Fix kfree() of static memory on setting driver_override
slimbus: qcom-ngd: Fix kfree() of static memory on setting
driver_override
rpmsg: Constify local variable in field store macro
rpmsg: Fix kfree() of static memory on setting driver_override

drivers/amba/bus.c | 28 ++------------
drivers/base/driver.c | 65 +++++++++++++++++++++++++++++++++
drivers/base/platform.c | 28 ++------------
drivers/bus/fsl-mc/fsl-mc-bus.c | 25 ++-----------
drivers/clk/imx/clk-scu.c | 7 +++-
drivers/hv/vmbus_drv.c | 28 ++------------
drivers/pci/pci-sysfs.c | 28 ++------------
drivers/rpmsg/rpmsg_core.c | 3 +-
drivers/rpmsg/rpmsg_internal.h | 13 ++++++-
drivers/rpmsg/rpmsg_ns.c | 14 ++++++-
drivers/s390/cio/cio.h | 6 ++-
drivers/s390/cio/css.c | 28 ++------------
drivers/slimbus/qcom-ngd-ctrl.c | 13 ++++++-
drivers/spi/spi.c | 26 ++-----------
drivers/vdpa/vdpa.c | 29 ++-------------
include/linux/amba/bus.h | 6 ++-
include/linux/device/driver.h | 2 +
include/linux/fsl/mc.h | 6 ++-
include/linux/hyperv.h | 6 ++-
include/linux/pci.h | 6 ++-
include/linux/platform_device.h | 6 ++-
include/linux/rpmsg.h | 6 ++-
include/linux/spi/spi.h | 2 +
include/linux/vdpa.h | 4 +-
24 files changed, 180 insertions(+), 205 deletions(-)

--
2.32.0