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 <luciano.coelho@xxxxxxxxx>
>
> 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 <luciano.coelho@xxxxxxxxx>
> Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
> ---
> 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;
> }
