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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CBC09C4332F for ; Mon, 7 Nov 2022 21:37:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232838AbiKGVhn (ORCPT ); Mon, 7 Nov 2022 16:37:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233514AbiKGVhn (ORCPT ); Mon, 7 Nov 2022 16:37:43 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B1A8D9; Mon, 7 Nov 2022 13:37:42 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DBF78612D5; Mon, 7 Nov 2022 21:37:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FDC7C433D6; Mon, 7 Nov 2022 21:37:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667857061; bh=T2Ymb2x245aa2ScFXcWkFua5HIUae1DGKTKUll+OBec=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=HdhozuACVbWX6bKTRIioUFaE5L3ZgEt4f5bqfJPjfhUL/TkWVTdFN8DBM9WwppI9m TXQLUZkj7BjVHq36fHM+6D3+Q+VNAABtzQ0jCbkQ5XvvMIkUw957s2HOLXhsC4Rmuq tJx0Bk2meKFUDRhTxpPOT5+gABL5tfBkAU0Oz/c7PuGPeEpPKrrGUpKPzgMRLQb2Wf MIXx2qqEnOHnUIpRt4mAer3Rln01RG+rMGKcOW28zGs1Po482XYwBMCutR6QhgvoX2 jBWgY3uyK7whMZG+Z8XaAW/6+2EVrlLFVXy6k+QEuIscQMDZ5SQcGzmMmpZ2FHGjWq 4UXbGnuzlbuFA== Date: Mon, 7 Nov 2022 15:37:39 -0600 From: Bjorn Helgaas To: Kai-Heng Feng Cc: Christophe Fergeau , bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: Clear PCI_STATUS when setting up the device Message-ID: <20221107213739.GA422107@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221104155339.GA95864@bhelgaas> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Fri, Nov 04, 2022 at 10:53:39AM -0500, Bjorn Helgaas wrote: > On Tue, May 17, 2022 at 12:37:38PM +0800, Kai-Heng Feng wrote: > > We are seeing Master Abort bit is set on Intel I350 ethernet device and its > > root port right after boot, probably happened during BIOS phase: > > > > 00:06.0 PCI bridge [0604]: Intel Corporation Device [8086:464d] (rev 05) (prog-if 00 [Normal decode]) > > Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- > > > 6e:00.0 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01) > > Subsystem: Intel Corporation Ethernet Server Adapter I350-T2 [8086:00a2] > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- > > > 6e:00.1 Ethernet controller [0200]: Intel Corporation I350 Gigabit Network Connection [8086:1521] (rev 01) > > Subsystem: Intel Corporation Ethernet Server Adapter I350-T2 [8086:00a2] > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- > > > And the Master Abort bit is cleared after S3. > > > > Since there's no functional impact found, clear the PCI_STATUS to treat > > it anew at setting up. > > > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215989 > > Signed-off-by: Kai-Heng Feng > > This patch appeared in v6.0 as 6cd514e58f12 ("PCI: Clear PCI_STATUS > when setting up device"). Christophe reported in the bugzilla that it > causes boot failures: > > > --- Comment #3 from Christophe Fergeau (cfergeau@redhat.com) --- > > This commit > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6c > > d514e58f12b211d638dbf6f791fa18d854f09c > > references this issue. > > This commit causes boot failures when trying to start linux guests with Apple's > > hypervisor framework (for example using https://github.com/evansm7/vftool ). > > After reverting it, I can successfully boot 6.1-rc kernels on my macOS12 x86_64 > > macbook. With this commit, the VM fails to start, additional details in > > https://bugzilla.redhat.com/show_bug.cgi?id=2137803 I queued up a revert for v6.2. Obviously I would prefer if we could figure out how to clear PCI_STATUS while still letting the guests boot, but I have no idea how to debug the boot failures. commit 44e985938e85 ("Revert "PCI: Clear PCI_STATUS when setting up device"") Author: Bjorn Helgaas Date: Mon Nov 7 15:31:08 2022 -0600 Revert "PCI: Clear PCI_STATUS when setting up device" This reverts commit 6cd514e58f12b211d638dbf6f791fa18d854f09c. Christophe Fergeau reported that 6cd514e58f12 ("PCI: Clear PCI_STATUS when setting up device") causes boot failures when trying to start linux guests with Apple's virtualization framework (for example using https://developer.apple.com/documentation/virtualization/running_linux_in_a_virtual_machine?language=objc) 6cd514e58f12 only solved a cosmetic problem, so revert it to fix the boot failures. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2137803 Signed-off-by: Bjorn Helgaas diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index b66fa42c4b1f..1d6f7b502020 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1891,9 +1891,6 @@ int pci_setup_device(struct pci_dev *dev) dev->broken_intx_masking = pci_intx_mask_broken(dev); - /* Clear errors left from system firmware */ - pci_write_config_word(dev, PCI_STATUS, 0xffff); - switch (dev->hdr_type) { /* header type */ case PCI_HEADER_TYPE_NORMAL: /* standard header */ if (class == PCI_CLASS_BRIDGE_PCI) > > --- > > drivers/pci/probe.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > > index 17a969942d370..414f659dc8735 100644 > > --- a/drivers/pci/probe.c > > +++ b/drivers/pci/probe.c > > @@ -1890,6 +1890,9 @@ int pci_setup_device(struct pci_dev *dev) > > > > dev->broken_intx_masking = pci_intx_mask_broken(dev); > > > > + /* Clear errors left from system firmware */ > > + pci_write_config_word(dev, PCI_STATUS, 0xffff); > > + > > switch (dev->hdr_type) { /* header type */ > > case PCI_HEADER_TYPE_NORMAL: /* standard header */ > > if (class == PCI_CLASS_BRIDGE_PCI) > > -- > > 2.34.1 > >