From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:47394 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728086AbeJSB7o (ORCPT ); Thu, 18 Oct 2018 21:59:44 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jisheng Zhang , Lorenzo Pieralisi , Bjorn Helgaas , Gustavo Pimentel , Sasha Levin Subject: [PATCH 4.18 30/53] PCI: dwc: Fix scheduling while atomic issues Date: Thu, 18 Oct 2018 19:54:23 +0200 Message-Id: <20181018175422.066166427@linuxfoundation.org> In-Reply-To: <20181018175416.561567978@linuxfoundation.org> References: <20181018175416.561567978@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jisheng Zhang [ Upstream commit 9024143e700f89d74b8cdaf316a3499d74fc56fe ] When programming the inbound/outbound ATUs, we call usleep_range() after each checking PCIE_ATU_ENABLE bit. Unfortunately, the ATU programming can be executed in atomic context: inbound ATU programming could be called through pci_epc_write_header() =>dw_pcie_ep_write_header() =>dw_pcie_prog_inbound_atu() outbound ATU programming could be called through pci_bus_read_config_dword() =>dw_pcie_rd_conf() =>dw_pcie_prog_outbound_atu() Fix this issue by calling mdelay() instead. Fixes: f8aed6ec624f ("PCI: dwc: designware: Add EP mode support") Fixes: d8bbeb39fbf3 ("PCI: designware: Wait for iATU enable") Signed-off-by: Jisheng Zhang [lorenzo.pieralisi@arm.com: commit log update] Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Acked-by: Gustavo Pimentel Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/pci/controller/dwc/pcie-designware.c | 8 ++++---- drivers/pci/controller/dwc/pcie-designware.h | 3 +-- 2 files changed, 5 insertions(+), 6 deletions(-) --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -135,7 +135,7 @@ static void dw_pcie_prog_outbound_atu_un if (val & PCIE_ATU_ENABLE) return; - usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX); + mdelay(LINK_WAIT_IATU); } dev_err(pci->dev, "Outbound iATU is not being enabled\n"); } @@ -178,7 +178,7 @@ void dw_pcie_prog_outbound_atu(struct dw if (val & PCIE_ATU_ENABLE) return; - usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX); + mdelay(LINK_WAIT_IATU); } dev_err(pci->dev, "Outbound iATU is not being enabled\n"); } @@ -236,7 +236,7 @@ static int dw_pcie_prog_inbound_atu_unro if (val & PCIE_ATU_ENABLE) return 0; - usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX); + mdelay(LINK_WAIT_IATU); } dev_err(pci->dev, "Inbound iATU is not being enabled\n"); @@ -282,7 +282,7 @@ int dw_pcie_prog_inbound_atu(struct dw_p if (val & PCIE_ATU_ENABLE) return 0; - usleep_range(LINK_WAIT_IATU_MIN, LINK_WAIT_IATU_MAX); + mdelay(LINK_WAIT_IATU); } dev_err(pci->dev, "Inbound iATU is not being enabled\n"); --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -26,8 +26,7 @@ /* Parameters for the waiting for iATU enabled routine */ #define LINK_WAIT_MAX_IATU_RETRIES 5 -#define LINK_WAIT_IATU_MIN 9000 -#define LINK_WAIT_IATU_MAX 10000 +#define LINK_WAIT_IATU 9 /* Synopsys-specific PCIe configuration registers */ #define PCIE_PORT_LINK_CONTROL 0x710