From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751659Ab3LABVt (ORCPT ); Sat, 30 Nov 2013 20:21:49 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:59022 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751373Ab3LABVo (ORCPT ); Sat, 30 Nov 2013 20:21:44 -0500 From: "Rafael J. Wysocki" To: netdev@vger.kernel.org Cc: LKML , Linux PM list , Linux PCI , Bjorn Helgaas , Nithin Nayak Sujir , Michael Chan , David Miller Subject: [PATCH] PCI / tg3: Give up chip reset and carrier loss handling if PCI device is not present Date: Sun, 01 Dec 2013 02:34:37 +0100 Message-ID: <7807315.7cU9KldDtM@vostro.rjw.lan> User-Agent: KMail/4.10.5 (Linux/3.12.0-rc6+; KDE/4.10.5; x86_64; ; ) MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki Modify tg3_chip_reset() and tg3_close() to check if the PCI network adapter device is accessible at all in order to skip poking it or trying to handle a carrier loss in vain when that's not the case. Introduce a special PCI helper function pci_device_is_present() for this purpose. Of course, this uncovers the lack of the appropriate RTNL locking in tg3_suspend() and tg3_resume(), so add that locking in there too. These changes prevent tg3 from burning a CPU at 100% load level for solid several seconds after the Thunderbolt link is disconnected from a Matrox DS1 docking station. Signed-off-by: Rafael J. Wysocki --- drivers/net/ethernet/broadcom/tg3.c | 26 +++++++++++++++++++------- drivers/pci/pci.c | 8 ++++++++ include/linux/pci.h | 1 + 3 files changed, 28 insertions(+), 7 deletions(-) Index: linux-pm/drivers/net/ethernet/broadcom/tg3.c =================================================================== --- linux-pm.orig/drivers/net/ethernet/broadcom/tg3.c +++ linux-pm/drivers/net/ethernet/broadcom/tg3.c @@ -8932,6 +8932,9 @@ static int tg3_chip_reset(struct tg3 *tp void (*write_op)(struct tg3 *, u32, u32); int i, err; + if (!pci_device_is_present(tp->pdev)) + return -ENODEV; + tg3_nvram_lock(tp); tg3_ape_lock(tp, TG3_APE_LOCK_GRC); @@ -11594,10 +11597,11 @@ static int tg3_close(struct net_device * memset(&tp->net_stats_prev, 0, sizeof(tp->net_stats_prev)); memset(&tp->estats_prev, 0, sizeof(tp->estats_prev)); - tg3_power_down_prepare(tp); - - tg3_carrier_off(tp); + if (pci_device_is_present(tp->pdev)) { + tg3_power_down_prepare(tp); + tg3_carrier_off(tp); + } return 0; } @@ -17739,10 +17743,12 @@ static int tg3_suspend(struct device *de struct pci_dev *pdev = to_pci_dev(device); struct net_device *dev = pci_get_drvdata(pdev); struct tg3 *tp = netdev_priv(dev); - int err; + int err = 0; + + rtnl_lock(); if (!netif_running(dev)) - return 0; + goto unlock; tg3_reset_task_cancel(tp); tg3_phy_stop(tp); @@ -17784,6 +17790,8 @@ out: tg3_phy_start(tp); } +unlock: + rtnl_unlock(); return err; } @@ -17792,10 +17800,12 @@ static int tg3_resume(struct device *dev struct pci_dev *pdev = to_pci_dev(device); struct net_device *dev = pci_get_drvdata(pdev); struct tg3 *tp = netdev_priv(dev); - int err; + int err = 0; + + rtnl_lock(); if (!netif_running(dev)) - return 0; + goto unlock; netif_device_attach(dev); @@ -17819,6 +17829,8 @@ out: if (!err) tg3_phy_start(tp); +unlock: + rtnl_unlock(); return err; } #endif /* CONFIG_PM_SLEEP */ Index: linux-pm/drivers/pci/pci.c =================================================================== --- linux-pm.orig/drivers/pci/pci.c +++ linux-pm/drivers/pci/pci.c @@ -4171,6 +4171,14 @@ int pci_set_vga_state(struct pci_dev *de return 0; } +bool pci_device_is_present(struct pci_dev *pdev) +{ + u32 v; + + return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0); +} +EXPORT_SYMBOL_GPL(pci_device_is_present); + #define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0}; static DEFINE_SPINLOCK(resource_alignment_lock); Index: linux-pm/include/linux/pci.h =================================================================== --- linux-pm.orig/include/linux/pci.h +++ linux-pm/include/linux/pci.h @@ -961,6 +961,7 @@ void pci_update_resource(struct pci_dev int __must_check pci_assign_resource(struct pci_dev *dev, int i); int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align); int pci_select_bars(struct pci_dev *dev, unsigned long flags); +bool pci_device_is_present(struct pci_dev *pdev); /* ROM control related routines */ int pci_enable_rom(struct pci_dev *pdev);