No description
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Jakob Hauser 0e421cb808 iio: magnetometer: yas530: use signed integer type for clamp limits
[ Upstream commit f1ee5483e4 ]

In the function yas537_measure() there is a clamp_val() with limits of
-BIT(13) and BIT(13) - 1.  The input clamp value h[] is of type s32.  The
BIT() is of type unsigned long integer due to its define in
include/vdso/bits.h.  The lower limit -BIT(13) is recognized as -8192 but
expressed as an unsigned long integer.  The size of an unsigned long
integer differs between 32-bit and 64-bit architectures.  Converting this
to type s32 may lead to undesired behavior.

Additionally, in the calculation lines h[0], h[1] and h[2] the unsigned
long integer divisor BIT(13) causes an unsigned division, shifting the
left-hand side of the equation back and forth, possibly ending up in large
positive values instead of negative values on 32-bit architectures.

To solve those two issues, declare a signed integer with a value of
BIT(13).

There is another omission in the clamp line: clamp_val() returns a value
and it's going nowhere here.  Self-assign it to h[i] to make use of the
clamp macro.

Finally, replace clamp_val() macro by clamp() because after changing the
limits from type unsigned long integer to signed integer it's fine that
way.

Link: https://lkml.kernel.org/r/11609b2243c295d65ab4d47e78c239d61ad6be75.1732914810.git.jahau@rocketmail.com
Fixes: 65f79b5010 ("iio: magnetometer: yas530: Add YAS537 variant")
Signed-off-by: Jakob Hauser <jahau@rocketmail.com>

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202411230458.dhZwh3TT-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202411282222.oF0B4110-lkp@intel.com/
Reviewed-by: David Laight <david.laight@aculab.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-12-14 20:03:19 +01:00
arch
block
certs
crypto
Documentation
drivers
fs
include
init
io_uring
ipc
kernel
lib
LICENSES
mm
net
rust
samples
scripts
security
sound
tools
usr
virt
.clang-format
.cocciconfig
.editorconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README

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
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText 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.