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 0D7B7C43334 for ; Wed, 8 Jun 2022 01:53:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378804AbiFHBtl (ORCPT ); Tue, 7 Jun 2022 21:49:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383641AbiFGWGF (ORCPT ); Tue, 7 Jun 2022 18:06:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7716019595B; Tue, 7 Jun 2022 12:16:49 -0700 (PDT) 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 04F86618EC; Tue, 7 Jun 2022 19:16:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1505DC385A2; Tue, 7 Jun 2022 19:16:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654629408; bh=BUUyuJwqsmQ8ppwNkzVju8FLysHPnnjZRg/0W7ctp2w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rn9/RqC8NPobfc98cJ811h3yVaUeCELZhnTfRZzWTdFcfJX3KXJeFgclZ4BCkw5dh x84YajPMFrDE9GcBQsXeudYHz3qBY1ENWTnvrm0ob8WaUwnZ33xlA9WQ5gsNs8j3YQ kQy/lwr0fOnz03MhE4eGV5ucED6jDFcludvhlDII= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Badger , Kuppuswamy Sathyanarayanan , Bjorn Helgaas , Ashok Raj , Sasha Levin Subject: [PATCH 5.18 630/879] PCI/AER: Clear MULTI_ERR_COR/UNCOR_RCV bits Date: Tue, 7 Jun 2022 19:02:28 +0200 Message-Id: <20220607165021.136028307@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607165002.659942637@linuxfoundation.org> References: <20220607165002.659942637@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kuppuswamy Sathyanarayanan [ Upstream commit 203926da2bff8e172200a2f11c758987af112d4a ] When a Root Port or Root Complex Event Collector receives an error Message e.g., ERR_COR, it sets PCI_ERR_ROOT_COR_RCV in the Root Error Status register and logs the Requester ID in the Error Source Identification register. If it receives a second ERR_COR Message before software clears PCI_ERR_ROOT_COR_RCV, hardware sets PCI_ERR_ROOT_MULTI_COR_RCV and the Requester ID is lost. In the following scenario, PCI_ERR_ROOT_MULTI_COR_RCV was never cleared: - hardware receives ERR_COR message - hardware sets PCI_ERR_ROOT_COR_RCV - aer_irq() entered - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS) - aer_irq(): now status == PCI_ERR_ROOT_COR_RCV - hardware receives second ERR_COR message - hardware sets PCI_ERR_ROOT_MULTI_COR_RCV - aer_irq(): pci_write_config_dword(PCI_ERR_ROOT_STATUS, status) - PCI_ERR_ROOT_COR_RCV is cleared; PCI_ERR_ROOT_MULTI_COR_RCV is set - aer_irq() entered again - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS) - aer_irq(): now status == PCI_ERR_ROOT_MULTI_COR_RCV - aer_irq() exits because PCI_ERR_ROOT_COR_RCV not set - PCI_ERR_ROOT_MULTI_COR_RCV is still set The same problem occurred with ERR_NONFATAL/ERR_FATAL Messages and PCI_ERR_ROOT_UNCOR_RCV and PCI_ERR_ROOT_MULTI_UNCOR_RCV. Fix the problem by queueing an AER event and clearing the Root Error Status bits when any of these bits are set: PCI_ERR_ROOT_COR_RCV PCI_ERR_ROOT_UNCOR_RCV PCI_ERR_ROOT_MULTI_COR_RCV PCI_ERR_ROOT_MULTI_UNCOR_RCV See the bugzilla link for details from Eric about how to reproduce this problem. [bhelgaas: commit log, move repro details to bugzilla] Fixes: e167bfcaa4cd ("PCI: aerdrv: remove magical ROOT_ERR_STATUS_MASKS") Link: https://bugzilla.kernel.org/show_bug.cgi?id=215992 Link: https://lore.kernel.org/r/20220418150237.1021519-1-sathyanarayanan.kuppuswamy@linux.intel.com Reported-by: Eric Badger Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Bjorn Helgaas Reviewed-by: Ashok Raj Signed-off-by: Sasha Levin --- drivers/pci/pcie/aer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index 9fa1f97e5b27..7952e5efd6cf 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -101,6 +101,11 @@ struct aer_stats { #define ERR_COR_ID(d) (d & 0xffff) #define ERR_UNCOR_ID(d) (d >> 16) +#define AER_ERR_STATUS_MASK (PCI_ERR_ROOT_UNCOR_RCV | \ + PCI_ERR_ROOT_COR_RCV | \ + PCI_ERR_ROOT_MULTI_COR_RCV | \ + PCI_ERR_ROOT_MULTI_UNCOR_RCV) + static int pcie_aer_disable; static pci_ers_result_t aer_root_reset(struct pci_dev *dev); @@ -1196,7 +1201,7 @@ static irqreturn_t aer_irq(int irq, void *context) struct aer_err_source e_src = {}; pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status); - if (!(e_src.status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV))) + if (!(e_src.status & AER_ERR_STATUS_MASK)) return IRQ_NONE; pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id); -- 2.35.1