Ooops, I obviously meant "PATCH v2 09/12" in the subject. -- Luca.
On Thu, 2018-04-26 at 10:53 +0300, Luca Coelho wrote: > From: Luca Coelho <[email protected]> > > If we fail to to grab NIC access because the device is not responding > (i.e. CSR_GP_CNTRL returns 0xFFFFFFFF), remove the device from the > PCI > bus, to avoid any further damage, and to let the user space rescan. > > In order to inform the userspace that a rescan is needed, we send a > kobject uevent with "INACCESSIBLE". > > This functionality is disabled by default, but can be enabled via a > new module parameter called "remove_when_gone". In the future we may > change this module parameter to include 3 modes instead: do nothing; > auto-rescan or; send uevent. > > Signed-off-by: Luca Coelho <[email protected]> > Signed-off-by: Rajat Jain <[email protected]> > --- > drivers/net/wireless/intel/iwlwifi/iwl-drv.c | 6 ++ > .../wireless/intel/iwlwifi/iwl-modparams.h | 2 + > .../wireless/intel/iwlwifi/pcie/internal.h | 5 ++ > .../net/wireless/intel/iwlwifi/pcie/trans.c | 74 > ++++++++++++++++++- > 4 files changed, 84 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c > b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c > index 4f451a6f20b9..c59ce4f8a5ed 100644 > --- a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c > +++ b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c > @@ -1850,3 +1850,9 @@ MODULE_PARM_DESC(d0i3_timeout, "Timeout to D0i3 > entry when idle (ms)"); > > module_param_named(disable_11ac, iwlwifi_mod_params.disable_11ac, > bool, 0444); > MODULE_PARM_DESC(disable_11ac, "Disable VHT capabilities (default: > false)"); > + > +module_param_named(remove_when_gone, > + iwlwifi_mod_params.remove_when_gone, bool, > + 0444); > +MODULE_PARM_DESC(remove_when_gone, > + "Remove dev from PCIe bus if it is deemed > inaccessible (default: false)"); > diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h > b/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h > index a41c46e63eb1..a7dd8a8cddf9 100644 > --- a/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h > +++ b/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h > @@ -122,6 +122,7 @@ enum iwl_uapsd_disable { > * @lar_disable: disable LAR (regulatory), default = 0 > * @fw_monitor: allow to use firmware monitor > * @disable_11ac: disable VHT capabilities, default = false. > + * @remove_when_gone: remove an inaccessible device from the PCIe > bus. > */ > struct iwl_mod_params { > int swcrypto; > @@ -143,6 +144,7 @@ struct iwl_mod_params { > bool lar_disable; > bool fw_monitor; > bool disable_11ac; > + bool remove_when_gone; > }; > > #endif /* #__iwl_modparams_h__ */ > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > index cda66340d357..45ea32796cda 100644 > --- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h > @@ -383,6 +383,8 @@ struct iwl_self_init_dram { > * @hw_init_mask: initial unmasked hw causes > * @fh_mask: current unmasked fh causes > * @hw_mask: current unmasked hw causes > + * @in_rescan: true if we have triggered a device rescan > + * @scheduled_for_removal: true if we have scheduled a device > removal > */ > struct iwl_trans_pcie { > struct iwl_rxq *rxq; > @@ -464,6 +466,9 @@ struct iwl_trans_pcie { > u32 fh_mask; > u32 hw_mask; > cpumask_t affinity_mask[IWL_MAX_RX_HW_QUEUES]; > + u16 tx_cmd_queue_size; > + bool in_rescan; > + bool scheduled_for_removal; > }; > > static inline struct iwl_trans_pcie * > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > index 623476603cd4..6e9a9ecfb11c 100644 > --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c > @@ -75,6 +75,7 @@ > #include <linux/gfp.h> > #include <linux/vmalloc.h> > #include <linux/pm_runtime.h> > +#include <linux/module.h> > > #include "iwl-drv.h" > #include "iwl-trans.h" > @@ -1935,6 +1936,29 @@ static void iwl_trans_pcie_set_pmi(struct > iwl_trans *trans, bool state) > clear_bit(STATUS_TPOWER_PMI, &trans->status); > } > > +struct iwl_trans_pcie_removal { > + struct pci_dev *pdev; > + struct work_struct work; > +}; > + > +static void iwl_trans_pcie_removal_wk(struct work_struct *wk) > +{ > + struct iwl_trans_pcie_removal *removal = > + container_of(wk, struct iwl_trans_pcie_removal, > work); > + struct pci_dev *pdev = removal->pdev; > + char *prop[] = {"EVENT=INACCESSIBLE", NULL}; > + > + dev_err(&pdev->dev, "Device gone - attempting removal\n"); > + kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, prop); > + pci_lock_rescan_remove(); > + pci_dev_put(pdev); > + pci_stop_and_remove_bus_device(pdev); > + pci_unlock_rescan_remove(); > + > + kfree(removal); > + module_put(THIS_MODULE); > +} > + > static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans, > unsigned long *flags) > { > @@ -1977,11 +2001,55 @@ static bool > iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans, > (BIT(trans->cfg->csr- > >flag_mac_clock_ready) | > CSR_GP_CNTRL_REG_FLAG_GOING_TO_SLEEP), > 15000); > if (unlikely(ret < 0)) { > - iwl_trans_pcie_dump_regs(trans); > - iwl_write32(trans, CSR_RESET, > CSR_RESET_REG_FLAG_FORCE_NMI); > + u32 cntrl = iwl_read32(trans, CSR_GP_CNTRL); > + > WARN_ONCE(1, > "Timeout waiting for hardware access > (CSR_GP_CNTRL 0x%08x)\n", > - iwl_read32(trans, CSR_GP_CNTRL)); > + cntrl); > + > + iwl_trans_pcie_dump_regs(trans); > + > + if (iwlwifi_mod_params.remove_when_gone && cntrl == > ~0U) { > + struct iwl_trans_pcie_removal *removal; > + > + if (trans_pcie->scheduled_for_removal) > + goto err; > + > + IWL_ERR(trans, "Device gone - scheduling > removal!\n"); > + > + /* > + * get a module reference to avoid doing > this > + * while unloading anyway and to avoid > + * scheduling a work with code that's being > + * removed. > + */ > + if (!try_module_get(THIS_MODULE)) { > + IWL_ERR(trans, > + "Module is being unloaded - > abort\n"); > + goto err; > + } > + > + removal = kzalloc(sizeof(*removal), > GFP_ATOMIC); > + if (!removal) { > + module_put(THIS_MODULE); > + goto err; > + } > + /* > + * we don't need to clear this flag, because > + * the trans will be freed and reallocated. > + */ > + trans_pcie->scheduled_for_removal = true; > + > + removal->pdev = to_pci_dev(trans->dev); > + INIT_WORK(&removal->work, > iwl_trans_pcie_removal_wk); > + pci_dev_get(removal->pdev); > + schedule_work(&removal->work); > + } else { > + iwl_write32(trans, CSR_RESET, > + CSR_RESET_REG_FLAG_FORCE_NMI); > + } > + > +err: > spin_unlock_irqrestore(&trans_pcie->reg_lock, > *flags); > return false; > }
