Return-path: Received: from mail-we0-f181.google.com ([74.125.82.181]:54657 "EHLO mail-we0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753883AbaAFPHw (ORCPT ); Mon, 6 Jan 2014 10:07:52 -0500 Received: by mail-we0-f181.google.com with SMTP id x55so15440856wes.26 for ; Mon, 06 Jan 2014 07:07:51 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1389020664.5891.18.camel@jlt4.sipsolutions.net> References: <82A67CC48AF04D43A69EB66645975134107C6285@hbmail01.hb.imgtec.org> <1389020664.5891.18.camel@jlt4.sipsolutions.net> From: Krishna Chaitanya Date: Mon, 6 Jan 2014 20:37:30 +0530 Message-ID: (sfid-20140106_160755_223855_93C64C67) Subject: Re: [PATCH] mac80211: Return untuned timestamp in case of invalid bitrates To: Johannes Berg Cc: Chaitanya Tata , "linux-wireless@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Mon, Jan 6, 2014 at 8:34 PM, Johannes Berg wrote: > On Thu, 2013-12-26 at 13:42 +0000, Chaitanya Tata wrote: >> In case the driver sends MCS9 and doesn't advertise CBW >> (or) advertises 20MHz bandwidth, return the timestamp As is, >> instead of returning 0 as timestamp. >> >> Signed-off-by: Chaitanya T K >> --- >> net/mac80211/util.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 06265d7..bc92b25 100644 >> --- a/net/mac80211/util.c >> +++ b/net/mac80211/util.c >> @@ -2265,7 +2265,7 @@ u64 ieee80211_calculate_rx_timestamp(struct ieee80211_local *local, >> if (WARN_ONCE(!rate, >> "Invalid bitrate: flags=0x%x, idx=%d, vht_nss=%d\n", >> status->flag, status->rate_idx, status->vht_nss)) >> - return 0; >> + return ts; > > I think this is wrong - we've already warned, we know we have no usable > timestamp, and this should never happen anyway. Timestamp is just off by packet length (as we dont have proper MCS rates), but still we can use it as un-rewinded timestamp.