On Tue, 2019-03-12 at 14:58 +0800, maowenan wrote: > On 2019/3/12 14:35, Joe Perches wrote: > > On Tue, 2019-03-12 at 14:29 +0800, maowenan wrote: > > > ping... > > > > > > On 2019/3/9 11:26, Mao Wenan wrote: > > > > Using is_zero_ether_addr() instead of directly use > > > > memcmp() to determine if the ethernet address is all > > > > zeros. > > [] > > > > diff --git a/drivers/staging/rtl8188eu/core/rtw_mlme.c b/drivers/staging/rtl8188eu/core/rtw_mlme.c > > [] > > > > @@ -180,9 +180,8 @@ struct wlan_network *rtw_find_network(struct __queue *scanned_queue, u8 *addr) > > > > { > > > > struct list_head *phead, *plist; > > > > struct wlan_network *pnetwork = NULL; > > > > - u8 zero_addr[ETH_ALEN] = {0, 0, 0, 0, 0, 0}; > > > > > > > > - if (!memcmp(zero_addr, addr, ETH_ALEN)) { > > > > + if (is_zero_ether_addr(addr)) { > > > > How did you verify that addr is __aligned(2)? > > /** > * is_zero_ether_addr - Determine if give Ethernet address is all zeros. > * @addr: Pointer to a six-byte array containing the Ethernet address > * > * Return true if the address is all zeroes. > */ > I think they are completely equivalent functions, no need to check addr is __aligned(2), > because addr may be defined as unsigned char MacAddress[ETH_ALEN]; the length is 6. Perhaps you are reading old documentation. (though the "Please note:" line is from 2013) include/linux/etherdevice.h-/** include/linux/etherdevice.h- * is_zero_ether_addr - Determine if give Ethernet address is all zeros. include/linux/etherdevice.h- * @addr: Pointer to a six-byte array containing the Ethernet address include/linux/etherdevice.h- * include/linux/etherdevice.h- * Return true if the address is all zeroes. include/linux/etherdevice.h- * include/linux/etherdevice.h- * Please note: addr must be aligned to u16. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel