From 8496e85c20e7836b3dec97780e40f420a3ae2801 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 1 Dec 2013 02:34:37 +0100 Subject: [PATCH] PCI / tg3: Give up chip reset and carrier loss handling if PCI device is not present 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 Acked-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/tg3.c | 26 +++++++++++++++++++------- drivers/pci/pci.c | 8 ++++++++ include/linux/pci.h | 1 + 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c index 369b736dde05..472305cdff4f 100644 --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/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); @@ -11581,10 +11584,11 @@ static int tg3_close(struct net_device *dev) 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; } @@ -17726,10 +17730,12 @@ static int tg3_suspend(struct device *device) 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); @@ -17771,6 +17777,8 @@ static int tg3_suspend(struct device *device) tg3_phy_start(tp); } +unlock: + rtnl_unlock(); return err; } @@ -17779,10 +17787,12 @@ static int tg3_resume(struct device *device) 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); @@ -17806,6 +17816,8 @@ static int tg3_resume(struct device *device) if (!err) tg3_phy_start(tp); +unlock: + rtnl_unlock(); return err; } #endif /* CONFIG_PM_SLEEP */ diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 33120d156668..07369f32e8bb 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4165,6 +4165,14 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, 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); diff --git a/include/linux/pci.h b/include/linux/pci.h index 1084a15175e0..25a389566e47 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -960,6 +960,7 @@ void pci_update_resource(struct pci_dev *dev, int resno); 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); -- GitLab