Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758176AbaAGAEF (ORCPT ); Mon, 6 Jan 2014 19:04:05 -0500 Received: from mail-ie0-f180.google.com ([209.85.223.180]:57317 "EHLO mail-ie0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756857AbaAGAEB (ORCPT ); Mon, 6 Jan 2014 19:04:01 -0500 MIME-Version: 1.0 In-Reply-To: References: <52B0AEAD.6050604@gmail.com> <20131218010207.GC15119@google.com> From: Bjorn Helgaas Date: Mon, 6 Jan 2014 17:03:39 -0700 Message-ID: Subject: Re: [PATCH v3 4/8] pciehp: Don't disable the link permanently, during removal To: Rajat Jain Cc: Rajat Jain , Kenji Kaneshige , Alex Williamson , Yijing Wang , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Yinghai Lu , Guenter Roeck , Rajat Jain , Yinghai Lu Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jan 5, 2014 at 10:53 AM, Rajat Jain wrote: > Hello Bjorn, > > Just checking on the fate of this patch set... > > On Tue, Dec 17, 2013 at 5:02 PM, Bjorn Helgaas wrote: >> [+cc yinghai@kernel.org (seems to be Yinghai's preferred email] >> >> On Tue, Dec 17, 2013 at 12:06:05PM -0800, Rajat Jain wrote: >>> We need future link up events for hot-add, thus don't disable >>> the link permanently during device removal. Also, remove the static >>> functions that are now left unused. >> >> The changelog should mention that this reverts part of 2debd9289997 ("PCI: >> pciehp: Disable/enable link during slot power off/on"). > > Sure. Do you want me to submit another patch set (bumping up the > version) with this change log, or you'd want to add this change log > while merging? > >> >> Yinghai, can you tell us whether this is an issue on your systems? > > As Yinghai confirms further down this thread, his issue was confirmed > by Intel to be a bug in the repeater chip. > ---------------------------------- > Yinghai writes: >> According to HW guys and Intel, that should be bug of repeater. >> > --------------------------------- > I don't know about the details of his scenario, except that when the > adapter was disabled the repeater kept on flapping the link up & down > (and hence disabling the link solved the problem then). Yinghai > couldn't test, but I believe with this patch even if we disable > presence detect interrupt, the "adapter present / no present" messages > would (rightly) convert to "Link Up / Link Down" messages (since the > repeater keeps on flapping the link). > > Since it is a platform specific bug, I'm not sure what can be done to > remove those messages except may be reduce the verbosity? If you'd > like I could change all the INFO messages to DBG messages. Even if it's a defect in a particular piece of hardware, I don't want to regress on that hardware, even if the regression is just extra messages that we didn't see before. I think ideally we would add some sort of quirk for that hardware so it works just as well as it does today. I think extra messages will lead to a bug reports from users. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/