From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Subject: [PATCH] 2.6.25-rc4 de_stop_rxtx polling wrong Date: Sat, 8 Mar 2008 18:33:16 -0700 Message-ID: <20080309013316.GD25083@colo.lackof.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, akpm@linux-foundation.org To: jgarzik@pobox.org Return-path: Received: from colo.lackof.org ([198.49.126.79]:48761 "EHLO colo.lackof.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752494AbYCIBd2 (ORCPT ); Sat, 8 Mar 2008 20:33:28 -0500 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Jeff, This untested patch _should_ fix: "(net de2104x) Kernel panic with de2104x tulip driver on boot" http://bugzilla.kernel.org/show_bug.cgi?id=3156 But the bug submitter isn't responding. Same fix has been applied to tulip.c (several years ago) and uli526x.c (Feb 2008) drivers. Patch was originally against 2.6.23 but applies clean against 2.6.25-rc4. [ The panic reported in the bug report was removed in a recently (march 2008) accepted patch from Ondrej Zary. ] Signed-off-by: Grant Grundler --- linux-2.6.23/drivers/net/tulip/de2104x.c 2007-10-09 13:31:38.000000000 -0700 +++ linux-2.6.23/drivers/net/tulip/de2104x.c-ggg 2007-11-02 23:24:46.000000000 -0700 @@ -842,7 +842,7 @@ static void de_stop_rxtx (struct de_private *de) { u32 macmode; - unsigned int work = 1000; + unsigned int i = 1300/100; macmode = dr32(MacMode); if (macmode & RxTx) { @@ -850,10 +850,14 @@ dr32(MacMode); } - while (--work > 0) { + /* wait until in-flight frame completes. + * Max time @ 10BT: 1500*8b/10Mbps == 1200us (+ 100us margin) + * Typically expect this loop to end in < 50 us on 100BT. + */ + while (--i) { if (!de_is_running(de)) return; - cpu_relax(); + udelay(100); } printk(KERN_WARNING "%s: timeout expired stopping DMA\n", de->dev->name);