From: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 14 Feb 2023 16:25:36 +0100
Subject: [PATCH] ethernet: ice: avoid gcc-9 integer overflow warning
References: bsc#1012628
Patch-mainline: 6.2.7
Git-commit: 8f5c5a790e3025d6eca96bf7ee5e3873dc92373f
[ 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>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/net/ethernet/intel/ice/ice_tc_lib.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_tc_lib.c b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
index 95f392ab..ce72d512 100644
--- a/drivers/net/ethernet/intel/ice/ice_tc_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_tc_lib.c
@@ -1448,8 +1448,8 @@ ice_parse_cls_flower(struct net_device *filter_dev, struct ice_vsi *vsi,
if (match.mask->vlan_priority) {
fltr->flags |= ICE_TC_FLWR_FIELD_VLAN_PRIO;
headers->vlan_hdr.vlan_prio =
- cpu_to_be16((match.key->vlan_priority <<
- VLAN_PRIO_SHIFT) & VLAN_PRIO_MASK);
+ be16_encode_bits(match.key->vlan_priority,
+ VLAN_PRIO_MASK);
}
if (match.mask->vlan_tpid)
@@ -1482,8 +1482,8 @@ ice_parse_cls_flower(struct net_device *filter_dev, struct ice_vsi *vsi,
if (match.mask->vlan_priority) {
fltr->flags |= ICE_TC_FLWR_FIELD_CVLAN_PRIO;
headers->cvlan_hdr.vlan_prio =
- cpu_to_be16((match.key->vlan_priority <<
- VLAN_PRIO_SHIFT) & VLAN_PRIO_MASK);
+ be16_encode_bits(match.key->vlan_priority,
+ VLAN_PRIO_MASK);
}
}
--
2.35.3