Return-path: Received: from mms1.broadcom.com ([216.31.210.17]:3931 "EHLO mms1.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750838AbXE2PhQ (ORCPT ); Tue, 29 May 2007 11:37:16 -0400 Subject: Re: b44: regression in 2.6.22 (resend) From: "Gary Zambrano" To: "Michael Buesch" cc: "Maximilian Engelhardt" , "linux-kernel" , "linux-wireless" , "Stephen Hemminger" , "Arnaldo Carvalho de Melo" , "Jeff Garzik" , netdev@vger.kernel.org, "Andrew Morton" In-Reply-To: <200705281655.15105.mb@bu3sch.de> References: <20070525172431.60affaca@freepuppy> <200705281249.56106.mb@bu3sch.de> <200705281612.15649.maxi@daemonizer.de> <200705281655.15105.mb@bu3sch.de> Date: Tue, 29 May 2007 07:14:35 -0700 Message-ID: <1180448075.17146.12.camel@dhcp-10-12-136-115.broadcom.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: On Mon, 2007-05-28 at 16:55 +0200, Michael Buesch wrote: > On Monday 28 May 2007 16:12:12 Maximilian Engelhardt wrote: > > On Monday 28 May 2007, Michael Buesch wrote: > > > Can you also test the following patch? > > > I think there's a bug in b44 that is doesn't properly discard > > > shared IRQs, so it might possibly generate a NAPI storm, dunno. > > > Worth a try. > > > > > > Index: linux-2.6.22-rc3/drivers/net/b44.c > > > =================================================================== > > > --- linux-2.6.22-rc3.orig/drivers/net/b44.c 2007-05-27 23:01:44.000000000 > > > +0200 +++ linux-2.6.22-rc3/drivers/net/b44.c 2007-05-28 12:48:27.000000000 > > > +0200 @@ -911,6 +911,8 @@ static irqreturn_t b44_interrupt(int irq > > > spin_lock(&bp->lock); > > > > > > istat = br32(bp, B44_ISTAT); > > > + if (istat == 0xFFFFFFFF) > > > + goto out; /* Shared IRQ not for us */ > > > imask = br32(bp, B44_IMASK); > > > > > > /* The interrupt mask register controls which interrupt bits > > > @@ -942,6 +944,7 @@ irq_ack: > > > bw32(bp, B44_ISTAT, istat); > > > br32(bp, B44_ISTAT); > > > } > > > +out: > > > spin_unlock(&bp->lock); > > > return IRQ_RETVAL(handled); > > > } > > > > I did try this patch on a affected kernel, but I didn't notice any big > > difference. Perhaps the kernel is a bit less slow during the test, but It's > > hard to tell. > > Ok, but anyway. I think this is a bug and needs to be fixed this way. Gary? > Thanks Michael. No, I don't think this is a bug and it does not need to be fixed. Thanks, Gary