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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B96DEC6FA82 for ; Mon, 26 Sep 2022 18:09:47 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4MbrPk0XgGz3c1v for ; Tue, 27 Sep 2022 04:09:46 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=cc2VTt5Y; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=145.40.68.75; helo=ams.source.kernel.org; envelope-from=helgaas@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=cc2VTt5Y; dkim-atps=neutral Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4MbrP44fBJz3bNj for ; Tue, 27 Sep 2022 04:09:12 +1000 (AEST) 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 ams.source.kernel.org (Postfix) with ESMTPS id 4206BB80BA3; Mon, 26 Sep 2022 18:09:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF6A3C433D6; Mon, 26 Sep 2022 18:09:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664215748; bh=f0vC5rcbDYjIyScqcWYY9GpgiQN1RROu0ZZ2a2E8E2U=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=cc2VTt5YU8CMoAICIdScy9zbs3OhBWuctGyV31uYoLdX/jhHdprUjUqxyrBZ90I2m h8N5ESFrH1aB8IMAdw2dYD0NCdAYmVAWblgzCt/FgA6kr9H6dIGoOFJ3yX0nTLyyk7 gb35oRC9yB3dTEzhLGg/AhrJGiOmlbX2LU1buRJYTRbUORZAxUyRtFt0UpbZ75PkX2 qC0+M6pIGnpbu+rX6ewu3bb5iebRbHY/rA+em1+StX155rtK6dt5K5tLJbhb+c0LDc fbLcwRJOPUksuwO/XnLcreVRekt5Z59jz5qMlcdMO7KxrNiaxg692INePg4DaFbIMu 2iLGYmd1p3aOQ== Date: Mon, 26 Sep 2022 13:09:06 -0500 From: Bjorn Helgaas To: Zhuo Chen Subject: Re: [PATCH 2/3] PCI/ERR: Clear fatal status in pcie_do_recovery() Message-ID: <20220926180906.GA1609498@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1de80c28-33ec-b1bd-a557-91e4166d2da7@bytedance.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: allenbh@gmail.com, dave.jiang@intel.com, linux-scsi@vger.kernel.org, martin.petersen@oracle.com, linux-pci@vger.kernel.org, jejb@linux.ibm.com, james.smart@broadcom.com, fancer.lancer@gmail.com, linux-kernel@vger.kernel.org, ntb@lists.linux.dev, oohall@gmail.com, jdmason@kudzu.us, bhelgaas@google.com, dick.kennedy@broadcom.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Sep 26, 2022 at 10:01:55PM +0800, Zhuo Chen wrote: > On 9/23/22 5:08 AM, Bjorn Helgaas wrote: > > On Fri, Sep 02, 2022 at 02:16:33AM +0800, Zhuo Chen wrote: > > > When state is pci_channel_io_frozen in pcie_do_recovery(), > > > the severity is fatal and fatal status should be cleared. > > > So we add pci_aer_clear_fatal_status(). > > > > Seems sensible to me. Did you find this by code inspection or by > > debugging a problem? If the latter, it would be nice to mention the > > symptoms of the problem in the commit log. > > I found this by code inspection so I may not enumerate what kind of problems > this code will cause. > > > > > Since pcie_aer_is_native() in pci_aer_clear_fatal_status() > > > and pci_aer_clear_nonfatal_status() contains the function of > > > 'if (host->native_aer || pcie_ports_native)', so we move them > > > out of it. > > > > Wrap commit log to fill 75 columns. > > > > > Signed-off-by: Zhuo Chen > > > --- > > > drivers/pci/pcie/err.c | 8 ++++++-- > > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > > > index 0c5a143025af..e0a8ade4c3fe 100644 > > > --- a/drivers/pci/pcie/err.c > > > +++ b/drivers/pci/pcie/err.c > > > @@ -243,10 +243,14 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > > > * it is responsible for clearing this status. In that case, the > > > * signaling device may not even be visible to the OS. > > > */ > > > - if (host->native_aer || pcie_ports_native) { > > > + if (host->native_aer || pcie_ports_native) > > > pcie_clear_device_status(dev); > > > > pcie_clear_device_status() doesn't check for pcie_aer_is_native() > > internally, but after 068c29a248b6 ("PCI/ERR: Clear PCIe Device Status > > errors only if OS owns AER") and aa344bc8b727 ("PCI/ERR: Clear AER > > status only when we control AER"), both callers check before calling > > it. > > > > I think we should move the check inside pcie_clear_device_status(). > > That could be a separate preliminary patch. > > > > There are a couple other places (aer_root_reset() and > > get_port_device_capability()) that do the same check and could be > > changed to use pcie_aer_is_native() instead. That could be another > > preliminary patch. > > > Good suggestion. But I have only one doubt. In aer_root_reset(), if we use > "if (pcie_aer_is_native(dev) && aer)", when dev->aer_cap > is NULL and root->aer_cap is not NULL, pcie_aer_is_native() will return > false. It's different from just using "(host->native_aer || > pcie_ports_native)". > Or if we can use "if (pcie_aer_is_native(root))", at this time a NULL > pointer check should be added in pcie_aer_is_native() because root may be > NULL. Good point. In aer_root_reset(), we're updating Root Port registers, so I think they should look like: if (pcie_aer_is_native(root) && aer) { ... } Does that seem safe and equivalent to you? Bjorn