diff options
| author | Thierry Reding <treding@nvidia.com> | 2019-02-06 15:30:18 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-02-07 00:40:08 +0300 |
| commit | deedf1feb255c7a390309f615e50de37cb82fb61 (patch) | |
| tree | 6bd19596f8d8862ae28b99259db0c62ae7f24ab2 /drivers | |
| parent | 04c7788c2bb3542e5c8c9d7175193e4d925edf20 (diff) | |
| download | linux-deedf1feb255c7a390309f615e50de37cb82fb61.tar.xz | |
r8169: Avoid pointer aliasing
Read MAC address 32-bit at a time and manually extract the individual
bytes. This avoids pointer aliasing and gives the compiler a better
chance of optimizing the operation.
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/realtek/r8169.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c index 501891be7c56..1dd72137fd53 100644 --- a/drivers/net/ethernet/realtek/r8169.c +++ b/drivers/net/ethernet/realtek/r8169.c @@ -7113,12 +7113,21 @@ static int rtl_alloc_irq(struct rtl8169_private *tp) static void rtl_read_mac_address(struct rtl8169_private *tp, u8 mac_addr[ETH_ALEN]) { + u32 value; + /* Get MAC address */ switch (tp->mac_version) { case RTL_GIGA_MAC_VER_35 ... RTL_GIGA_MAC_VER_38: case RTL_GIGA_MAC_VER_40 ... RTL_GIGA_MAC_VER_51: - *(u32 *)&mac_addr[0] = rtl_eri_read(tp, 0xe0, ERIAR_EXGMAC); - *(u16 *)&mac_addr[4] = rtl_eri_read(tp, 0xe4, ERIAR_EXGMAC); + value = rtl_eri_read(tp, 0xe0, ERIAR_EXGMAC); + mac_addr[0] = (value >> 0) & 0xff; + mac_addr[1] = (value >> 8) & 0xff; + mac_addr[2] = (value >> 16) & 0xff; + mac_addr[3] = (value >> 24) & 0xff; + + value = rtl_eri_read(tp, 0xe4, ERIAR_EXGMAC); + mac_addr[4] = (value >> 0) & 0xff; + mac_addr[5] = (value >> 8) & 0xff; break; default: break; @@ -7316,7 +7325,8 @@ static int rtl_get_ether_clk(struct rtl8169_private *tp) static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) { const struct rtl_cfg_info *cfg = rtl_cfg_infos + ent->driver_data; - u8 mac_addr[ETH_ALEN] __aligned(4) = {}; + /* align to u16 for is_valid_ether_addr() */ + u8 mac_addr[ETH_ALEN] __aligned(2) = {}; struct rtl8169_private *tp; struct net_device *dev; int chipset, region, i; |