From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5FFAFC433FE for ; Thu, 7 Oct 2021 12:15:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 437086125F for ; Thu, 7 Oct 2021 12:15:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241257AbhJGMRC (ORCPT ); Thu, 7 Oct 2021 08:17:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:54516 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241251AbhJGMRB (ORCPT ); Thu, 7 Oct 2021 08:17:01 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4CEC561037; Thu, 7 Oct 2021 12:15:08 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mYSIk-00FJDn-F2; Thu, 07 Oct 2021 13:15:06 +0100 Date: Thu, 07 Oct 2021 13:15:05 +0100 Message-ID: <878rz5qbee.wl-maz@kernel.org> From: Marc Zyngier To: Rui Salvaterra Cc: tglx@linutronix.de, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [REGRESSION][BISECTED] 5.15-rc1: Broken AHCI on NVIDIA ION (MCP79) In-Reply-To: References: <87ee8yquyi.wl-maz@kernel.org> <87bl41qkrh.wl-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: rsalvaterra@gmail.com, tglx@linutronix.de, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, 07 Oct 2021 13:03:28 +0100, Rui Salvaterra wrote: > > Hi again, Marc, > > On Thu, 7 Oct 2021 at 09:52, Marc Zyngier wrote: > > > [snipped] > > > > I guess this is the relevant device? > > Pretty much, yes. > > > It is interesting that it > > advertises not supporting interrupt masking... Can you, you, out of > > curiosity, give the following hack a go? I would expect things to > > behave badly too (and maybe be even worse). But one way or another, it > > may give us a hint. > > > > Thanks, > > > > M. > > > > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > > index 0099a00af361..b3c0b9d07f17 100644 > > --- a/drivers/pci/msi.c > > +++ b/drivers/pci/msi.c > > @@ -205,7 +205,7 @@ static void __pci_msi_mask_desc(struct msi_desc *desc, u32 mask) > > > > if (desc->msi_attrib.is_msix) > > pci_msix_mask(desc); > > - else if (desc->msi_attrib.maskbit) > > + else //if (desc->msi_attrib.maskbit) > > pci_msi_mask(desc, mask); > > } > > > > @@ -216,7 +216,7 @@ static void __pci_msi_unmask_desc(struct msi_desc *desc, u32 mask) > > > > if (desc->msi_attrib.is_msix) > > pci_msix_unmask(desc); > > - else if (desc->msi_attrib.maskbit) > > + else //if (desc->msi_attrib.maskbit) > > pci_msi_unmask(desc, mask); > > } > > Hm. You belive the controller is lying? :) 'Believe' is not a word I'd use. I know for a fact that all HW, whether it is present, past or future is only a pile of hacks. Given that your report tends to indicate that we fail to enable the interrupt for this device, this would be a possibility. > Sure thing, I'll give it a spin and let you know the result. Thanks, M. -- Without deviation from the norm, progress is not possible.