From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Subject: Re: [PATCH net-next-2.6 1/2] be2net: Adding an option to use INTx instead of MSI-X Date: Wed, 27 Oct 2010 23:37:14 -0600 Message-ID: <20101028053714.GD32200@lackof.org> References: <1288075928.6578.185.camel@concordia> <20101026133233.GH15074@solarflare.com> <1288135235.16778.14.camel@concordia> <20101027.084604.226761472.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: michael@ellerman.id.au, bhutchings@solarflare.com, somnath.kotur@emulex.com, netdev@vger.kernel.org, linux-pci@vger.kernel.org To: David Miller Return-path: Content-Disposition: inline In-Reply-To: <20101027.084604.226761472.davem@davemloft.net> Sender: linux-pci-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Oct 27, 2010 at 08:46:04AM -0700, David Miller wrote: > From: Michael Ellerman > Date: Wed, 27 Oct 2010 10:20:35 +1100 > > > On Tue, 2010-10-26 at 14:32 +0100, Ben Hutchings wrote: > >> Michael Ellerman wrote: > >> > On Mon, 2010-10-25 at 16:25 -0700, David Miller wrote: > >> > > From: Ben Hutchings > >> > > Date: Mon, 25 Oct 2010 23:38:53 +0100 > > > >> > Ethtool would be nice, but only for network drivers. Is there a generic > >> > solution, quirks are obviously not keeping people happy. > >> > >> Since this is (normally) a property of the system, pci=nomsi is the > >> generic solution. > > > > Sort of, it's a big hammer. Did all these driver writers not know about > > pci=nomsi or did they prefer to add a parameter to their driver for some > > reason? > > Every time I've actually done the work to try and track down the > true issue, it always turned out to be a PCI chipset problem rather > than a device specific issue. I agree with your generalization. I can think of only one exception: ISTR pre-5705 tg3 chips would send both MSI and assert IRQ line at the same time. My guess is driver writers just want knob to "work around" any issues *their* driver might see with chipset. Disabling MSI for all drivers doesn't leave opportunity for experimenting with individual drivers. hth, grant > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html