net: Fix features skip in for_each_netdev_feature()
authorTariq Toukan <tariqt@nvidia.com>
Wed, 4 May 2022 08:09:14 +0000 (11:09 +0300)
committerJakub Kicinski <kuba@kernel.org>
Fri, 6 May 2022 01:25:57 +0000 (18:25 -0700)
The find_next_netdev_feature() macro gets the "remaining length",
not bit index.
Passing "bit - 1" for the following iteration is wrong as it skips
the adjacent bit. Pass "bit" instead.

Fixes: 3b89ea9c5902 ("net: Fix for_each_netdev_feature on Big endian")
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Link: https://lore.kernel.org/r/20220504080914.1918-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
include/linux/netdev_features.h

index 2c6b9e4..7c2d77d 100644 (file)
@@ -169,7 +169,7 @@ enum {
 #define NETIF_F_HW_HSR_FWD     __NETIF_F(HW_HSR_FWD)
 #define NETIF_F_HW_HSR_DUP     __NETIF_F(HW_HSR_DUP)
 
-/* Finds the next feature with the highest number of the range of start till 0.
+/* Finds the next feature with the highest number of the range of start-1 till 0.
  */
 static inline int find_next_netdev_feature(u64 feature, unsigned long start)
 {
@@ -188,7 +188,7 @@ static inline int find_next_netdev_feature(u64 feature, unsigned long start)
        for ((bit) = find_next_netdev_feature((mask_addr),              \
                                              NETDEV_FEATURE_COUNT);    \
             (bit) >= 0;                                                \
-            (bit) = find_next_netdev_feature((mask_addr), (bit) - 1))
+            (bit) = find_next_netdev_feature((mask_addr), (bit)))
 
 /* Features valid for ethtool to change */
 /* = all defined minus driver/device-class-related */