Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:37142 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752735AbYKSMeB (ORCPT ); Wed, 19 Nov 2008 07:34:01 -0500 Subject: Re: [PATCH/RFT] iwlagn: fix RX skb alignment From: Johannes Berg To: Tomas Winkler Cc: John Linville , reinette chatre , Marcel Holtmann , "Luis R. Rodriguez" , "Rafael J. Wysocki" , Matt Mackall , Christophe Dumez , Zhu Yi , Jan =?UTF-8?Q?V=C4=8Del=C3=A1k?= , Thomas Witt , linux-wireless , Andres Freund In-Reply-To: <1ba2fa240811190422o4eebb26ai17ea12825ae8e708@mail.gmail.com> (sfid-20081119_132259_432501_DF04DFBB) References: <1226969241.4014.24.camel@johannes.berg> <1227001390.4014.43.camel@johannes.berg> <1ba2fa240811180613g48c94199s67e4334e89282e76@mail.gmail.com> <1227021904.4014.58.camel@johannes.berg> <1ba2fa240811190115i6bad0c89wb1d9c8ee281be2f8@mail.gmail.com> <1227094594.26243.6.camel@johannes.berg> <1ba2fa240811190422o4eebb26ai17ea12825ae8e708@mail.gmail.com> (sfid-20081119_132259_432501_DF04DFBB) Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-COMhdIac1SKYgyBPgRqn" Date: Wed, 19 Nov 2008 13:33:13 +0100 Message-Id: <1227097994.26243.33.camel@johannes.berg> (sfid-20081119_133405_721470_4082DCD2) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-COMhdIac1SKYgyBPgRqn Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Wed, 2008-11-19 at 14:22 +0200, Tomas Winkler wrote: > > Yeah, it's weird, and it doesn't even seem to solve it for everyone. So > > there must be another thing too. >=20 > It seems that your wrong command queue problem is no the same root > cause we see on x86 platforms they have just same phenomena, because > there is 0xff data on the RX buffer. Well we've seen at one report that it helps, on x86. And the alignment thing is definitely a bug, so fixing it had to help somewhere. But yes, it looks like there's a different bug leading to the same symptoms elsewhere... Here's a thought: iwl_rx_queue_update_write_ptr doesn't synchronise the pointer rxq->bd memory to the device. So if you have a platform that's not cache coherent for IO devices (mine is) that might be a problem. johannes --=-COMhdIac1SKYgyBPgRqn Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Comment: Johannes Berg (powerbook) iQIcBAABAgAGBQJJJAeGAAoJEKVg1VMiehFYBIYP/10qZwjzpeBh3kkPmHVD+FtK Opv7ypd0Lb1WNPB1Yulzs6VHzmrYFlN8TozcpCTGjRYh+DJgDc/1jfZDJUetQmfK R7e32tBsED/YitU95sKa7LYGBbHAnY7LlLPWd6Ym/VhzsMrDktXHvxwC1zIYj7C/ xmwIQjNOsgJsxv6P1ePB/JmCR0nrdYgUoF0QrBIOnXBkjZ/6iJWcs2AGf3XA3Krs 7xzVGm7f/UUkPl6eu0SZ7ftptgRDZ5MZctXjkbkmllRzFA/cqUDEFIL+YeAdy582 w4U/hWosc13yRXkNmhKE2GbWC5UK8VpNsWguiUu9rUyRzzDoh8hdpsGWwRDAblQe VDTNtsMqnsQSrVj6+OajWI5rL5yp9ObeJXg9SE24GY8pdteVb3QUmWDRehGZaqRb xsVAtuvOYmPuFzXvWcCwktuO+BDj1itMnSuGDzQ1s3M5+ucndyuu4dl/t1ADsUjs SgDtiHs5K9bDNMVmWGiGs09ppMpVbDMi3kOTTCh2vPaknbC8MF3MdOFLtia01Ua8 LmBGIrsS+XxiF5MUKRrOtk5YrzSj7/ThhS6JCAiKWM+IRYhp1zIVusQBrYg7ChNR 4aUfOSayvUz1UJR5R9v4Rfj/B0sg9lLCz0ri6KCAnnI3Sp4SG+ANZyVxFIFLZ1zK n/YyQUZnM3hi0x/h01Ck =NuxJ -----END PGP SIGNATURE----- --=-COMhdIac1SKYgyBPgRqn--