1bd9219177
[ Upstream commit 8f5c5a790e3025d6eca96bf7ee5e3873dc92373f ]
With older compilers like gcc-9, the calculation of the vlan
priority field causes a false-positive warning from the byteswap:
In file included from drivers/net/ethernet/intel/ice/ice_tc_lib.c:4:
drivers/net/ethernet/intel/ice/ice_tc_lib.c: In function 'ice_parse_cls_flower':
include/uapi/linux/swab.h:15:15: error: integer overflow in expression '(int)(short unsigned int)((int)match.key-><U67c8>.<U6698>.vlan_priority << 13) & 57344 & 255' of type 'int' results in '0' [-Werror=overflow]
15 | (((__u16)(x) & (__u16)0x00ffU) << 8) | \
| ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
include/uapi/linux/swab.h:106:2: note: in expansion of macro '___constant_swab16'
106 | ___constant_swab16(x) : \
| ^~~~~~~~~~~~~~~~~~
include/uapi/linux/byteorder/little_endian.h:42:43: note: in expansion of macro '__swab16'
42 | #define __cpu_to_be16(x) ((__force __be16)__swab16((x)))
| ^~~~~~~~
include/linux/byteorder/generic.h:96:21: note: in expansion of macro '__cpu_to_be16'
96 | #define cpu_to_be16 __cpu_to_be16
| ^~~~~~~~~~~~~
drivers/net/ethernet/intel/ice/ice_tc_lib.c:1458:5: note: in expansion of macro 'cpu_to_be16'
1458 | cpu_to_be16((match.key->vlan_priority <<
| ^~~~~~~~~~~
After a change to be16_encode_bits(), the code becomes more
readable to both people and compilers, which avoids the warning.
Fixes: 34800178b302 ("ice: Add support for VLAN priority filters in switchdev")
Suggested-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
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
``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 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.