From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-io0-f179.google.com ([209.85.223.179]:36535 "EHLO mail-io0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756944AbcCCWhc convert rfc822-to-8bit (ORCPT ); Thu, 3 Mar 2016 17:37:32 -0500 Received: by mail-io0-f179.google.com with SMTP id l127so43929131iof.3 for ; Thu, 03 Mar 2016 14:37:32 -0800 (PST) MIME-Version: 1.0 Date: Thu, 3 Mar 2016 23:37:31 +0100 Message-ID: (sfid-20160303_233735_995351_C89C7240) Subject: Problem with brcmfmac removing extra interface From: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= To: brcm80211 development Cc: "linux-wireless@vger.kernel.org" , Brett Rudley , Arend van Spriel , "Franky (Zhenhui) Lin" , Hante Meuleman Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi, brcmfmac in general is not capable of removing interfaces. If you take a look at brcmf_cfg80211_del_iface implementation, you'll see it returns -EOPNOTSUPP (except for p2p interfaces). However there is problem in handling NL80211_CMD_STOP_AP (with the brcmf_cfg80211_stop_ap callback). Current implementation calls brcmf_fil_cmd_int_set(ifp, BRCMF_C_DOWN, 1) if mbss support is enabled/used. Above call results in firmware generating BRCMF_E_LINK event. This event is handled with the following forward-traced functions chain: 1) brcmf_notify_connect_status 2) brcmf_notify_connect_status_ap 3) brcmf_remove_interface 4) brcmf_del_if 5) brcmf_net_detach 6) unregister_netdev So the result of NL80211_CMD_STOP_AP is interface being removed. The problem with this behavior is that interface can't be recreated after that: # iw phy phy1 interface add wlan1-1 type __ap [ 3602.929199] brcmfmac: brcmf_ap_add_vif: timeout occurred command failed: I/O error (-5) I hit this problem when trying to restart hostapd using BCM43602 and 2 BSSes. Could you analyze this problem and see if you see some way of solving this problem, please? -- Rafał