From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9A7614A3D for ; Fri, 12 Jul 2024 11:42:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720784538; cv=none; b=SHomegNqATd8pNLnDv8CzfTDfrVGdni7o9azHzEIVQR94jPVw5iV5ly5lCpZrhMYw4FfQ6glWobtgA120LICgc45x6sBn6tqXSCDyHivu4xGgHBMIUgQDBIjli9ayY0vZzZ8PU3zgGx16gYcLfKvDfhqg9p19L+DZl9os4pvHUo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720784538; c=relaxed/simple; bh=Vyjy44iWXBUAtobZim+B+vF7TS8mewHUrZGQBPuJp0Q=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=VCdUnll24TjMEq71vlVFuhcaFRpKLV47+k9CYYyLggtCOF5YRHqKcrDBuhxkAuuA5btkebNq2mCuWUONoYDJkea8sR/fFhZHj5wmdPGmFu4tV46gAOk3nwsS2o8DwhwWgH09AQcDNWlkQY1+b02xmUz8frpprrxkzp3Kbbrd33E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AtwXpn0e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AtwXpn0e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C83FC32782; Fri, 12 Jul 2024 11:42:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720784538; bh=Vyjy44iWXBUAtobZim+B+vF7TS8mewHUrZGQBPuJp0Q=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=AtwXpn0eIi7syH5YQGAu5JEJjQ3SThv7T1OkcaJv64zZp2ZThUsIp9cwbwAbW1mFk OU9fIszhDX0lJGC6FuF1eWtbE1TU+WGW9F95JgYflwntpQtPc6FAVZ+0mrRtmJWc9a WfA1mm1L1E/IaoWRTFgVv6KFrJLQD71aeo0MIZBBxdruQn1QWaSC7rMHyxeijEEqMJ zqIsCXNsR7xwCIOHrWxiPkHP+/wS2SKfQhaFDUTelkBfy//lhw7YzAzVPPOs8jZtD9 8u5N3I0DlmkQeQYNEX9d5pXf8ybUFtmhJbhE2APqaq5VR1NtNpmEtYTSS8zuJAK4Mk caUoXekGds7lg== Date: Fri, 12 Jul 2024 06:42:16 -0500 From: Bjorn Helgaas To: dukovac.stefanie@live.ca Cc: linux-pci@vger.kernel.org Subject: Re: [Bug 219031] New: DPC Regression non-Root Port and non-RCEC devices Message-ID: <20240712114216.GA322718@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Jul 12, 2024 at 12:18:46AM +0000, bugzilla-daemon@kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=219031 > > Bug ID: 219031 > Summary: DPC Regression non-Root Port and non-RCEC devices > Product: Drivers > Version: 2.5 > Hardware: All > OS: Linux > Status: NEW > Severity: normal > Priority: P3 > Component: PCI > Assignee: drivers_pci@kernel-bugs.osdl.org > Reporter: dukovac.stefanie@live.ca > Regression: No > > Created attachment 306564 > --> https://bugzilla.kernel.org/attachment.cgi?id=306564&action=edit > Diff of lspci output of switch between 6.5 and 6.5 with native dpc > > This commit > https://lore.kernel.org/all/20221210002922.1749403-1-helgaas@kernel.org/ > assumes that "switch[es] supports AER but not MSI" so initializing the AER IQR > fails. This commit prevents registering AER and consequently DPC services on > non-Root Port, non-Root Complex Event Collector devices. > > I have a switch that supports MSI (or so I think). I find that DPC is no longer > enabled by default on the switch with this commit. To re-enable DPC I pass > `pcie_ports=dpc-native` as a karg. This means pci_aer_available() in on L263 of > portdrv.c must evaluate to true, which means pci_msi_enabled() must be true, > hence my switch does not match the assumption of the commit. > > The `pcie_ports=dpc-native` karg forces native DPC control, regardless of > whether native AER is enabled or not. PCIe r4.0 sec 6.1.10 and PCIe r7.0 sec > 6.2.11 both recommend the operating system always link DPC control to the > control of AER. > > I am working on 6.5.13. Thanks for the report. The change you mention was merged as https://git.kernel.org/linus/d8d2b65a940b ("PCI/portdrv: Allow AER service only for Root Ports & RCECs"), which appeared in v6.2, so it looks like this would be a regression between v6.1 and v6.2. Can you verify that v6.9 is still broken this way? It sounds like you've checked that reverting d8d2b65a940b solves the problem? Can you please attach the complete dmesg log from the newest kernel you can test?