![Bryant G. Ly](/assets/img/avatar_default.png)
Devices can go offline when erors reported. This patch adds a change to the kernel object and lets udev know of error. When device resumes, a change is also set reporting device as online. Therefore, EEH and AER events are better propagated to user space for PCI devices in all arches. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Juan J. Alvarez <jjalvare@linux.vnet.ibm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1076 lines
28 KiB
C
1076 lines
28 KiB
C
/*
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* PCI Error Recovery Driver for RPA-compliant PPC64 platform.
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* Copyright IBM Corp. 2004 2005
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* Copyright Linas Vepstas <linas@linas.org> 2004, 2005
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*
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* All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or (at
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* your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
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* NON INFRINGEMENT. See the GNU General Public License for more
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* details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*
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* Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
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*/
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#include <linux/delay.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/module.h>
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#include <linux/pci.h>
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#include <asm/eeh.h>
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#include <asm/eeh_event.h>
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#include <asm/ppc-pci.h>
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#include <asm/pci-bridge.h>
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#include <asm/prom.h>
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#include <asm/rtas.h>
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struct eeh_rmv_data {
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struct list_head edev_list;
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int removed;
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};
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/**
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* eeh_pcid_name - Retrieve name of PCI device driver
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* @pdev: PCI device
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*
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* This routine is used to retrieve the name of PCI device driver
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* if that's valid.
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*/
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static inline const char *eeh_pcid_name(struct pci_dev *pdev)
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{
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if (pdev && pdev->dev.driver)
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return pdev->dev.driver->name;
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return "";
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}
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/**
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* eeh_pcid_get - Get the PCI device driver
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* @pdev: PCI device
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*
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* The function is used to retrieve the PCI device driver for
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* the indicated PCI device. Besides, we will increase the reference
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* of the PCI device driver to prevent that being unloaded on
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* the fly. Otherwise, kernel crash would be seen.
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*/
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static inline struct pci_driver *eeh_pcid_get(struct pci_dev *pdev)
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{
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if (!pdev || !pdev->driver)
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return NULL;
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if (!try_module_get(pdev->driver->driver.owner))
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return NULL;
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return pdev->driver;
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}
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/**
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* eeh_pcid_put - Dereference on the PCI device driver
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* @pdev: PCI device
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*
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* The function is called to do dereference on the PCI device
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* driver of the indicated PCI device.
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*/
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static inline void eeh_pcid_put(struct pci_dev *pdev)
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{
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if (!pdev || !pdev->driver)
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return;
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module_put(pdev->driver->driver.owner);
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}
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/**
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* eeh_disable_irq - Disable interrupt for the recovering device
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* @dev: PCI device
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*
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* This routine must be called when reporting temporary or permanent
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* error to the particular PCI device to disable interrupt of that
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* device. If the device has enabled MSI or MSI-X interrupt, we needn't
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* do real work because EEH should freeze DMA transfers for those PCI
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* devices encountering EEH errors, which includes MSI or MSI-X.
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*/
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static void eeh_disable_irq(struct pci_dev *dev)
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{
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struct eeh_dev *edev = pci_dev_to_eeh_dev(dev);
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/* Don't disable MSI and MSI-X interrupts. They are
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* effectively disabled by the DMA Stopped state
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* when an EEH error occurs.
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*/
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if (dev->msi_enabled || dev->msix_enabled)
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return;
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if (!irq_has_action(dev->irq))
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return;
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edev->mode |= EEH_DEV_IRQ_DISABLED;
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disable_irq_nosync(dev->irq);
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}
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/**
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* eeh_enable_irq - Enable interrupt for the recovering device
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* @dev: PCI device
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*
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* This routine must be called to enable interrupt while failed
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* device could be resumed.
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*/
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static void eeh_enable_irq(struct pci_dev *dev)
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{
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struct eeh_dev *edev = pci_dev_to_eeh_dev(dev);
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if ((edev->mode) & EEH_DEV_IRQ_DISABLED) {
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edev->mode &= ~EEH_DEV_IRQ_DISABLED;
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/*
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* FIXME !!!!!
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*
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* This is just ass backwards. This maze has
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* unbalanced irq_enable/disable calls. So instead of
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* finding the root cause it works around the warning
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* in the irq_enable code by conditionally calling
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* into it.
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*
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* That's just wrong.The warning in the core code is
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* there to tell people to fix their asymmetries in
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* their own code, not by abusing the core information
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* to avoid it.
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*
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* I so wish that the assymetry would be the other way
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* round and a few more irq_disable calls render that
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* shit unusable forever.
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*
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* tglx
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*/
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if (irqd_irq_disabled(irq_get_irq_data(dev->irq)))
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enable_irq(dev->irq);
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}
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}
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static bool eeh_dev_removed(struct eeh_dev *edev)
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{
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/* EEH device removed ? */
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if (!edev || (edev->mode & EEH_DEV_REMOVED))
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return true;
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return false;
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}
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static void *eeh_dev_save_state(void *data, void *userdata)
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{
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struct eeh_dev *edev = data;
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struct pci_dev *pdev;
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if (!edev)
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return NULL;
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/*
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* We cannot access the config space on some adapters.
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* Otherwise, it will cause fenced PHB. We don't save
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* the content in their config space and will restore
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* from the initial config space saved when the EEH
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* device is created.
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*/
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if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED))
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return NULL;
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pdev = eeh_dev_to_pci_dev(edev);
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if (!pdev)
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return NULL;
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pci_save_state(pdev);
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return NULL;
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}
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/**
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* eeh_report_error - Report pci error to each device driver
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* @data: eeh device
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* @userdata: return value
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*
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* Report an EEH error to each device driver, collect up and
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* merge the device driver responses. Cumulative response
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* passed back in "userdata".
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*/
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static void *eeh_report_error(void *data, void *userdata)
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{
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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enum pci_ers_result rc, *res = userdata;
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struct pci_driver *driver;
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if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
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return NULL;
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dev->error_state = pci_channel_io_frozen;
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driver = eeh_pcid_get(dev);
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if (!driver) return NULL;
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eeh_disable_irq(dev);
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if (!driver->err_handler ||
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!driver->err_handler->error_detected) {
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eeh_pcid_put(dev);
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return NULL;
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}
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rc = driver->err_handler->error_detected(dev, pci_channel_io_frozen);
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/* A driver that needs a reset trumps all others */
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if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
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if (*res == PCI_ERS_RESULT_NONE) *res = rc;
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edev->in_error = true;
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eeh_pcid_put(dev);
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pci_uevent_ers(dev, PCI_ERS_RESULT_NONE);
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return NULL;
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}
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/**
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* eeh_report_mmio_enabled - Tell drivers that MMIO has been enabled
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* @data: eeh device
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* @userdata: return value
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*
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* Tells each device driver that IO ports, MMIO and config space I/O
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* are now enabled. Collects up and merges the device driver responses.
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* Cumulative response passed back in "userdata".
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*/
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static void *eeh_report_mmio_enabled(void *data, void *userdata)
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{
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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enum pci_ers_result rc, *res = userdata;
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struct pci_driver *driver;
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if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
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return NULL;
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driver = eeh_pcid_get(dev);
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if (!driver) return NULL;
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if (!driver->err_handler ||
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!driver->err_handler->mmio_enabled ||
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(edev->mode & EEH_DEV_NO_HANDLER)) {
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eeh_pcid_put(dev);
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return NULL;
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}
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rc = driver->err_handler->mmio_enabled(dev);
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/* A driver that needs a reset trumps all others */
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if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
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if (*res == PCI_ERS_RESULT_NONE) *res = rc;
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eeh_pcid_put(dev);
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return NULL;
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}
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/**
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* eeh_report_reset - Tell device that slot has been reset
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* @data: eeh device
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* @userdata: return value
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*
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* This routine must be called while EEH tries to reset particular
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* PCI device so that the associated PCI device driver could take
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* some actions, usually to save data the driver needs so that the
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* driver can work again while the device is recovered.
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*/
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static void *eeh_report_reset(void *data, void *userdata)
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{
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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enum pci_ers_result rc, *res = userdata;
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struct pci_driver *driver;
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if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
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return NULL;
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dev->error_state = pci_channel_io_normal;
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driver = eeh_pcid_get(dev);
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if (!driver) return NULL;
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eeh_enable_irq(dev);
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if (!driver->err_handler ||
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!driver->err_handler->slot_reset ||
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(edev->mode & EEH_DEV_NO_HANDLER) ||
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(!edev->in_error)) {
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eeh_pcid_put(dev);
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return NULL;
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}
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rc = driver->err_handler->slot_reset(dev);
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if ((*res == PCI_ERS_RESULT_NONE) ||
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(*res == PCI_ERS_RESULT_RECOVERED)) *res = rc;
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if (*res == PCI_ERS_RESULT_DISCONNECT &&
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rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
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eeh_pcid_put(dev);
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return NULL;
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}
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static void *eeh_dev_restore_state(void *data, void *userdata)
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{
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struct eeh_dev *edev = data;
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struct pci_dev *pdev;
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if (!edev)
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return NULL;
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/*
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* The content in the config space isn't saved because
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* the blocked config space on some adapters. We have
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* to restore the initial saved config space when the
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* EEH device is created.
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*/
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if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED)) {
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if (list_is_last(&edev->list, &edev->pe->edevs))
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eeh_pe_restore_bars(edev->pe);
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return NULL;
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}
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pdev = eeh_dev_to_pci_dev(edev);
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if (!pdev)
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return NULL;
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pci_restore_state(pdev);
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return NULL;
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}
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/**
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* eeh_report_resume - Tell device to resume normal operations
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* @data: eeh device
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* @userdata: return value
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*
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* This routine must be called to notify the device driver that it
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* could resume so that the device driver can do some initialization
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* to make the recovered device work again.
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*/
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static void *eeh_report_resume(void *data, void *userdata)
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{
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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bool was_in_error;
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struct pci_driver *driver;
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if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
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return NULL;
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dev->error_state = pci_channel_io_normal;
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driver = eeh_pcid_get(dev);
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if (!driver) return NULL;
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was_in_error = edev->in_error;
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edev->in_error = false;
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eeh_enable_irq(dev);
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if (!driver->err_handler ||
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!driver->err_handler->resume ||
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(edev->mode & EEH_DEV_NO_HANDLER) || !was_in_error) {
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edev->mode &= ~EEH_DEV_NO_HANDLER;
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eeh_pcid_put(dev);
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return NULL;
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}
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driver->err_handler->resume(dev);
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eeh_pcid_put(dev);
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pci_uevent_ers(dev, PCI_ERS_RESULT_RECOVERED);
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#ifdef CONFIG_PCI_IOV
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eeh_ops->notify_resume(eeh_dev_to_pdn(edev));
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#endif
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return NULL;
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}
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/**
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* eeh_report_failure - Tell device driver that device is dead.
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* @data: eeh device
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* @userdata: return value
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*
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* This informs the device driver that the device is permanently
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* dead, and that no further recovery attempts will be made on it.
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*/
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static void *eeh_report_failure(void *data, void *userdata)
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{
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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struct pci_driver *driver;
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if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
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return NULL;
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dev->error_state = pci_channel_io_perm_failure;
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driver = eeh_pcid_get(dev);
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if (!driver) return NULL;
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eeh_disable_irq(dev);
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if (!driver->err_handler ||
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!driver->err_handler->error_detected) {
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eeh_pcid_put(dev);
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return NULL;
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}
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driver->err_handler->error_detected(dev, pci_channel_io_perm_failure);
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eeh_pcid_put(dev);
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pci_uevent_ers(dev, PCI_ERS_RESULT_DISCONNECT);
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return NULL;
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}
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static void *eeh_add_virt_device(void *data, void *userdata)
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{
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struct pci_driver *driver;
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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struct pci_dn *pdn = eeh_dev_to_pdn(edev);
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if (!(edev->physfn)) {
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pr_warn("%s: EEH dev %04x:%02x:%02x.%01x not for VF\n",
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__func__, pdn->phb->global_number, pdn->busno,
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PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
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return NULL;
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}
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driver = eeh_pcid_get(dev);
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if (driver) {
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eeh_pcid_put(dev);
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if (driver->err_handler)
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return NULL;
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}
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#ifdef CONFIG_PCI_IOV
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pci_iov_add_virtfn(edev->physfn, pdn->vf_index);
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#endif
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return NULL;
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}
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static void *eeh_rmv_device(void *data, void *userdata)
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{
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struct pci_driver *driver;
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struct eeh_dev *edev = (struct eeh_dev *)data;
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struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
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struct eeh_rmv_data *rmv_data = (struct eeh_rmv_data *)userdata;
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int *removed = rmv_data ? &rmv_data->removed : NULL;
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/*
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* Actually, we should remove the PCI bridges as well.
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* However, that's lots of complexity to do that,
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* particularly some of devices under the bridge might
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* support EEH. So we just care about PCI devices for
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* simplicity here.
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*/
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if (!dev || (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
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return NULL;
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/*
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* We rely on count-based pcibios_release_device() to
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* detach permanently offlined PEs. Unfortunately, that's
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* not reliable enough. We might have the permanently
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* offlined PEs attached, but we needn't take care of
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* them and their child devices.
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*/
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if (eeh_dev_removed(edev))
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return NULL;
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driver = eeh_pcid_get(dev);
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if (driver) {
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eeh_pcid_put(dev);
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if (removed &&
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eeh_pe_passed(edev->pe))
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return NULL;
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if (removed &&
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driver->err_handler &&
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driver->err_handler->error_detected &&
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driver->err_handler->slot_reset)
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return NULL;
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}
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/* Remove it from PCI subsystem */
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pr_debug("EEH: Removing %s without EEH sensitive driver\n",
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pci_name(dev));
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edev->bus = dev->bus;
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edev->mode |= EEH_DEV_DISCONNECTED;
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if (removed)
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(*removed)++;
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|
|
|
if (edev->physfn) {
|
|
#ifdef CONFIG_PCI_IOV
|
|
struct pci_dn *pdn = eeh_dev_to_pdn(edev);
|
|
|
|
pci_iov_remove_virtfn(edev->physfn, pdn->vf_index);
|
|
edev->pdev = NULL;
|
|
|
|
/*
|
|
* We have to set the VF PE number to invalid one, which is
|
|
* required to plug the VF successfully.
|
|
*/
|
|
pdn->pe_number = IODA_INVALID_PE;
|
|
#endif
|
|
if (rmv_data)
|
|
list_add(&edev->rmv_list, &rmv_data->edev_list);
|
|
} else {
|
|
pci_lock_rescan_remove();
|
|
pci_stop_and_remove_bus_device(dev);
|
|
pci_unlock_rescan_remove();
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void *eeh_pe_detach_dev(void *data, void *userdata)
|
|
{
|
|
struct eeh_pe *pe = (struct eeh_pe *)data;
|
|
struct eeh_dev *edev, *tmp;
|
|
|
|
eeh_pe_for_each_dev(pe, edev, tmp) {
|
|
if (!(edev->mode & EEH_DEV_DISCONNECTED))
|
|
continue;
|
|
|
|
edev->mode &= ~(EEH_DEV_DISCONNECTED | EEH_DEV_IRQ_DISABLED);
|
|
eeh_rmv_from_parent_pe(edev);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Explicitly clear PE's frozen state for PowerNV where
|
|
* we have frozen PE until BAR restore is completed. It's
|
|
* harmless to clear it for pSeries. To be consistent with
|
|
* PE reset (for 3 times), we try to clear the frozen state
|
|
* for 3 times as well.
|
|
*/
|
|
static void *__eeh_clear_pe_frozen_state(void *data, void *flag)
|
|
{
|
|
struct eeh_pe *pe = (struct eeh_pe *)data;
|
|
bool clear_sw_state = *(bool *)flag;
|
|
int i, rc = 1;
|
|
|
|
for (i = 0; rc && i < 3; i++)
|
|
rc = eeh_unfreeze_pe(pe, clear_sw_state);
|
|
|
|
/* Stop immediately on any errors */
|
|
if (rc) {
|
|
pr_warn("%s: Failure %d unfreezing PHB#%x-PE#%x\n",
|
|
__func__, rc, pe->phb->global_number, pe->addr);
|
|
return (void *)pe;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int eeh_clear_pe_frozen_state(struct eeh_pe *pe,
|
|
bool clear_sw_state)
|
|
{
|
|
void *rc;
|
|
|
|
rc = eeh_pe_traverse(pe, __eeh_clear_pe_frozen_state, &clear_sw_state);
|
|
if (!rc)
|
|
eeh_pe_state_clear(pe, EEH_PE_ISOLATED);
|
|
|
|
return rc ? -EIO : 0;
|
|
}
|
|
|
|
int eeh_pe_reset_and_recover(struct eeh_pe *pe)
|
|
{
|
|
int ret;
|
|
|
|
/* Bail if the PE is being recovered */
|
|
if (pe->state & EEH_PE_RECOVERING)
|
|
return 0;
|
|
|
|
/* Put the PE into recovery mode */
|
|
eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
|
|
|
|
/* Save states */
|
|
eeh_pe_dev_traverse(pe, eeh_dev_save_state, NULL);
|
|
|
|
/* Issue reset */
|
|
ret = eeh_pe_reset_full(pe);
|
|
if (ret) {
|
|
eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
|
|
return ret;
|
|
}
|
|
|
|
/* Unfreeze the PE */
|
|
ret = eeh_clear_pe_frozen_state(pe, true);
|
|
if (ret) {
|
|
eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
|
|
return ret;
|
|
}
|
|
|
|
/* Restore device state */
|
|
eeh_pe_dev_traverse(pe, eeh_dev_restore_state, NULL);
|
|
|
|
/* Clear recovery mode */
|
|
eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* eeh_reset_device - Perform actual reset of a pci slot
|
|
* @pe: EEH PE
|
|
* @bus: PCI bus corresponding to the isolcated slot
|
|
*
|
|
* This routine must be called to do reset on the indicated PE.
|
|
* During the reset, udev might be invoked because those affected
|
|
* PCI devices will be removed and then added.
|
|
*/
|
|
static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
|
|
struct eeh_rmv_data *rmv_data)
|
|
{
|
|
struct pci_bus *frozen_bus = eeh_pe_bus_get(pe);
|
|
time64_t tstamp;
|
|
int cnt, rc;
|
|
struct eeh_dev *edev;
|
|
|
|
/* pcibios will clear the counter; save the value */
|
|
cnt = pe->freeze_count;
|
|
tstamp = pe->tstamp;
|
|
|
|
/*
|
|
* We don't remove the corresponding PE instances because
|
|
* we need the information afterwords. The attached EEH
|
|
* devices are expected to be attached soon when calling
|
|
* into pci_hp_add_devices().
|
|
*/
|
|
eeh_pe_state_mark(pe, EEH_PE_KEEP);
|
|
if (bus) {
|
|
if (pe->type & EEH_PE_VF) {
|
|
eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
|
|
} else {
|
|
pci_lock_rescan_remove();
|
|
pci_hp_remove_devices(bus);
|
|
pci_unlock_rescan_remove();
|
|
}
|
|
} else if (frozen_bus) {
|
|
eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data);
|
|
}
|
|
|
|
/*
|
|
* Reset the pci controller. (Asserts RST#; resets config space).
|
|
* Reconfigure bridges and devices. Don't try to bring the system
|
|
* up if the reset failed for some reason.
|
|
*
|
|
* During the reset, it's very dangerous to have uncontrolled PCI
|
|
* config accesses. So we prefer to block them. However, controlled
|
|
* PCI config accesses initiated from EEH itself are allowed.
|
|
*/
|
|
rc = eeh_pe_reset_full(pe);
|
|
if (rc)
|
|
return rc;
|
|
|
|
pci_lock_rescan_remove();
|
|
|
|
/* Restore PE */
|
|
eeh_ops->configure_bridge(pe);
|
|
eeh_pe_restore_bars(pe);
|
|
|
|
/* Clear frozen state */
|
|
rc = eeh_clear_pe_frozen_state(pe, false);
|
|
if (rc) {
|
|
pci_unlock_rescan_remove();
|
|
return rc;
|
|
}
|
|
|
|
/* Give the system 5 seconds to finish running the user-space
|
|
* hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
|
|
* this is a hack, but if we don't do this, and try to bring
|
|
* the device up before the scripts have taken it down,
|
|
* potentially weird things happen.
|
|
*/
|
|
if (bus) {
|
|
pr_info("EEH: Sleep 5s ahead of complete hotplug\n");
|
|
ssleep(5);
|
|
|
|
/*
|
|
* The EEH device is still connected with its parent
|
|
* PE. We should disconnect it so the binding can be
|
|
* rebuilt when adding PCI devices.
|
|
*/
|
|
edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
|
|
eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
|
|
if (pe->type & EEH_PE_VF) {
|
|
eeh_add_virt_device(edev, NULL);
|
|
} else {
|
|
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
|
|
pci_hp_add_devices(bus);
|
|
}
|
|
} else if (frozen_bus && rmv_data->removed) {
|
|
pr_info("EEH: Sleep 5s ahead of partial hotplug\n");
|
|
ssleep(5);
|
|
|
|
edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
|
|
eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
|
|
if (pe->type & EEH_PE_VF)
|
|
eeh_add_virt_device(edev, NULL);
|
|
else
|
|
pci_hp_add_devices(frozen_bus);
|
|
}
|
|
eeh_pe_state_clear(pe, EEH_PE_KEEP);
|
|
|
|
pe->tstamp = tstamp;
|
|
pe->freeze_count = cnt;
|
|
|
|
pci_unlock_rescan_remove();
|
|
return 0;
|
|
}
|
|
|
|
/* The longest amount of time to wait for a pci device
|
|
* to come back on line, in seconds.
|
|
*/
|
|
#define MAX_WAIT_FOR_RECOVERY 300
|
|
|
|
/**
|
|
* eeh_handle_normal_event - Handle EEH events on a specific PE
|
|
* @pe: EEH PE
|
|
*
|
|
* Attempts to recover the given PE. If recovery fails or the PE has failed
|
|
* too many times, remove the PE.
|
|
*
|
|
* Returns true if @pe should no longer be used, else false.
|
|
*/
|
|
static bool eeh_handle_normal_event(struct eeh_pe *pe)
|
|
{
|
|
struct pci_bus *frozen_bus;
|
|
struct eeh_dev *edev, *tmp;
|
|
int rc = 0;
|
|
enum pci_ers_result result = PCI_ERS_RESULT_NONE;
|
|
struct eeh_rmv_data rmv_data = {LIST_HEAD_INIT(rmv_data.edev_list), 0};
|
|
|
|
frozen_bus = eeh_pe_bus_get(pe);
|
|
if (!frozen_bus) {
|
|
pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
|
|
__func__, pe->phb->global_number, pe->addr);
|
|
return false;
|
|
}
|
|
|
|
eeh_pe_update_time_stamp(pe);
|
|
pe->freeze_count++;
|
|
if (pe->freeze_count > eeh_max_freezes) {
|
|
pr_err("EEH: PHB#%x-PE#%x has failed %d times in the\n"
|
|
"last hour and has been permanently disabled.\n",
|
|
pe->phb->global_number, pe->addr,
|
|
pe->freeze_count);
|
|
goto hard_fail;
|
|
}
|
|
pr_warn("EEH: This PCI device has failed %d times in the last hour\n",
|
|
pe->freeze_count);
|
|
|
|
/* Walk the various device drivers attached to this slot through
|
|
* a reset sequence, giving each an opportunity to do what it needs
|
|
* to accomplish the reset. Each child gets a report of the
|
|
* status ... if any child can't handle the reset, then the entire
|
|
* slot is dlpar removed and added.
|
|
*
|
|
* When the PHB is fenced, we have to issue a reset to recover from
|
|
* the error. Override the result if necessary to have partially
|
|
* hotplug for this case.
|
|
*/
|
|
pr_info("EEH: Notify device drivers to shutdown\n");
|
|
eeh_pe_dev_traverse(pe, eeh_report_error, &result);
|
|
if ((pe->type & EEH_PE_PHB) &&
|
|
result != PCI_ERS_RESULT_NONE &&
|
|
result != PCI_ERS_RESULT_NEED_RESET)
|
|
result = PCI_ERS_RESULT_NEED_RESET;
|
|
|
|
/* Get the current PCI slot state. This can take a long time,
|
|
* sometimes over 300 seconds for certain systems.
|
|
*/
|
|
rc = eeh_ops->wait_state(pe, MAX_WAIT_FOR_RECOVERY*1000);
|
|
if (rc < 0 || rc == EEH_STATE_NOT_SUPPORT) {
|
|
pr_warn("EEH: Permanent failure\n");
|
|
goto hard_fail;
|
|
}
|
|
|
|
/* Since rtas may enable MMIO when posting the error log,
|
|
* don't post the error log until after all dev drivers
|
|
* have been informed.
|
|
*/
|
|
pr_info("EEH: Collect temporary log\n");
|
|
eeh_slot_error_detail(pe, EEH_LOG_TEMP);
|
|
|
|
/* If all device drivers were EEH-unaware, then shut
|
|
* down all of the device drivers, and hope they
|
|
* go down willingly, without panicing the system.
|
|
*/
|
|
if (result == PCI_ERS_RESULT_NONE) {
|
|
pr_info("EEH: Reset with hotplug activity\n");
|
|
rc = eeh_reset_device(pe, frozen_bus, NULL);
|
|
if (rc) {
|
|
pr_warn("%s: Unable to reset, err=%d\n",
|
|
__func__, rc);
|
|
goto hard_fail;
|
|
}
|
|
}
|
|
|
|
/* If all devices reported they can proceed, then re-enable MMIO */
|
|
if (result == PCI_ERS_RESULT_CAN_RECOVER) {
|
|
pr_info("EEH: Enable I/O for affected devices\n");
|
|
rc = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
|
|
|
|
if (rc < 0)
|
|
goto hard_fail;
|
|
if (rc) {
|
|
result = PCI_ERS_RESULT_NEED_RESET;
|
|
} else {
|
|
pr_info("EEH: Notify device drivers to resume I/O\n");
|
|
eeh_pe_dev_traverse(pe, eeh_report_mmio_enabled, &result);
|
|
}
|
|
}
|
|
|
|
/* If all devices reported they can proceed, then re-enable DMA */
|
|
if (result == PCI_ERS_RESULT_CAN_RECOVER) {
|
|
pr_info("EEH: Enabled DMA for affected devices\n");
|
|
rc = eeh_pci_enable(pe, EEH_OPT_THAW_DMA);
|
|
|
|
if (rc < 0)
|
|
goto hard_fail;
|
|
if (rc) {
|
|
result = PCI_ERS_RESULT_NEED_RESET;
|
|
} else {
|
|
/*
|
|
* We didn't do PE reset for the case. The PE
|
|
* is still in frozen state. Clear it before
|
|
* resuming the PE.
|
|
*/
|
|
eeh_pe_state_clear(pe, EEH_PE_ISOLATED);
|
|
result = PCI_ERS_RESULT_RECOVERED;
|
|
}
|
|
}
|
|
|
|
/* If any device has a hard failure, then shut off everything. */
|
|
if (result == PCI_ERS_RESULT_DISCONNECT) {
|
|
pr_warn("EEH: Device driver gave up\n");
|
|
goto hard_fail;
|
|
}
|
|
|
|
/* If any device called out for a reset, then reset the slot */
|
|
if (result == PCI_ERS_RESULT_NEED_RESET) {
|
|
pr_info("EEH: Reset without hotplug activity\n");
|
|
rc = eeh_reset_device(pe, NULL, &rmv_data);
|
|
if (rc) {
|
|
pr_warn("%s: Cannot reset, err=%d\n",
|
|
__func__, rc);
|
|
goto hard_fail;
|
|
}
|
|
|
|
pr_info("EEH: Notify device drivers "
|
|
"the completion of reset\n");
|
|
result = PCI_ERS_RESULT_NONE;
|
|
eeh_pe_dev_traverse(pe, eeh_report_reset, &result);
|
|
}
|
|
|
|
/* All devices should claim they have recovered by now. */
|
|
if ((result != PCI_ERS_RESULT_RECOVERED) &&
|
|
(result != PCI_ERS_RESULT_NONE)) {
|
|
pr_warn("EEH: Not recovered\n");
|
|
goto hard_fail;
|
|
}
|
|
|
|
/*
|
|
* For those hot removed VFs, we should add back them after PF get
|
|
* recovered properly.
|
|
*/
|
|
list_for_each_entry_safe(edev, tmp, &rmv_data.edev_list, rmv_list) {
|
|
eeh_add_virt_device(edev, NULL);
|
|
list_del(&edev->rmv_list);
|
|
}
|
|
|
|
/* Tell all device drivers that they can resume operations */
|
|
pr_info("EEH: Notify device driver to resume\n");
|
|
eeh_pe_dev_traverse(pe, eeh_report_resume, NULL);
|
|
|
|
return false;
|
|
|
|
hard_fail:
|
|
/*
|
|
* About 90% of all real-life EEH failures in the field
|
|
* are due to poorly seated PCI cards. Only 10% or so are
|
|
* due to actual, failed cards.
|
|
*/
|
|
pr_err("EEH: Unable to recover from failure from PHB#%x-PE#%x.\n"
|
|
"Please try reseating or replacing it\n",
|
|
pe->phb->global_number, pe->addr);
|
|
|
|
eeh_slot_error_detail(pe, EEH_LOG_PERM);
|
|
|
|
/* Notify all devices that they're about to go down. */
|
|
eeh_pe_dev_traverse(pe, eeh_report_failure, NULL);
|
|
|
|
/* Mark the PE to be removed permanently */
|
|
eeh_pe_state_mark(pe, EEH_PE_REMOVED);
|
|
|
|
/*
|
|
* Shut down the device drivers for good. We mark
|
|
* all removed devices correctly to avoid access
|
|
* the their PCI config any more.
|
|
*/
|
|
if (frozen_bus) {
|
|
if (pe->type & EEH_PE_VF) {
|
|
eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
|
|
eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
|
|
} else {
|
|
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
|
|
eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
|
|
|
|
pci_lock_rescan_remove();
|
|
pci_hp_remove_devices(frozen_bus);
|
|
pci_unlock_rescan_remove();
|
|
|
|
/* The passed PE should no longer be used */
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* eeh_handle_special_event - Handle EEH events without a specific failing PE
|
|
*
|
|
* Called when an EEH event is detected but can't be narrowed down to a
|
|
* specific PE. Iterates through possible failures and handles them as
|
|
* necessary.
|
|
*/
|
|
static void eeh_handle_special_event(void)
|
|
{
|
|
struct eeh_pe *pe, *phb_pe;
|
|
struct pci_bus *bus;
|
|
struct pci_controller *hose;
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
|
|
do {
|
|
rc = eeh_ops->next_error(&pe);
|
|
|
|
switch (rc) {
|
|
case EEH_NEXT_ERR_DEAD_IOC:
|
|
/* Mark all PHBs in dead state */
|
|
eeh_serialize_lock(&flags);
|
|
|
|
/* Purge all events */
|
|
eeh_remove_event(NULL, true);
|
|
|
|
list_for_each_entry(hose, &hose_list, list_node) {
|
|
phb_pe = eeh_phb_pe_get(hose);
|
|
if (!phb_pe) continue;
|
|
|
|
eeh_pe_state_mark(phb_pe, EEH_PE_ISOLATED);
|
|
}
|
|
|
|
eeh_serialize_unlock(flags);
|
|
|
|
break;
|
|
case EEH_NEXT_ERR_FROZEN_PE:
|
|
case EEH_NEXT_ERR_FENCED_PHB:
|
|
case EEH_NEXT_ERR_DEAD_PHB:
|
|
/* Mark the PE in fenced state */
|
|
eeh_serialize_lock(&flags);
|
|
|
|
/* Purge all events of the PHB */
|
|
eeh_remove_event(pe, true);
|
|
|
|
if (rc == EEH_NEXT_ERR_DEAD_PHB)
|
|
eeh_pe_state_mark(pe, EEH_PE_ISOLATED);
|
|
else
|
|
eeh_pe_state_mark(pe,
|
|
EEH_PE_ISOLATED | EEH_PE_RECOVERING);
|
|
|
|
eeh_serialize_unlock(flags);
|
|
|
|
break;
|
|
case EEH_NEXT_ERR_NONE:
|
|
return;
|
|
default:
|
|
pr_warn("%s: Invalid value %d from next_error()\n",
|
|
__func__, rc);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* For fenced PHB and frozen PE, it's handled as normal
|
|
* event. We have to remove the affected PHBs for dead
|
|
* PHB and IOC
|
|
*/
|
|
if (rc == EEH_NEXT_ERR_FROZEN_PE ||
|
|
rc == EEH_NEXT_ERR_FENCED_PHB) {
|
|
/*
|
|
* eeh_handle_normal_event() can make the PE stale if it
|
|
* determines that the PE cannot possibly be recovered.
|
|
* Don't modify the PE state if that's the case.
|
|
*/
|
|
if (eeh_handle_normal_event(pe))
|
|
continue;
|
|
|
|
eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
|
|
} else {
|
|
pci_lock_rescan_remove();
|
|
list_for_each_entry(hose, &hose_list, list_node) {
|
|
phb_pe = eeh_phb_pe_get(hose);
|
|
if (!phb_pe ||
|
|
!(phb_pe->state & EEH_PE_ISOLATED) ||
|
|
(phb_pe->state & EEH_PE_RECOVERING))
|
|
continue;
|
|
|
|
/* Notify all devices to be down */
|
|
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
|
|
eeh_pe_dev_traverse(pe,
|
|
eeh_report_failure, NULL);
|
|
bus = eeh_pe_bus_get(phb_pe);
|
|
if (!bus) {
|
|
pr_err("%s: Cannot find PCI bus for "
|
|
"PHB#%x-PE#%x\n",
|
|
__func__,
|
|
pe->phb->global_number,
|
|
pe->addr);
|
|
break;
|
|
}
|
|
pci_hp_remove_devices(bus);
|
|
}
|
|
pci_unlock_rescan_remove();
|
|
}
|
|
|
|
/*
|
|
* If we have detected dead IOC, we needn't proceed
|
|
* any more since all PHBs would have been removed
|
|
*/
|
|
if (rc == EEH_NEXT_ERR_DEAD_IOC)
|
|
break;
|
|
} while (rc != EEH_NEXT_ERR_NONE);
|
|
}
|
|
|
|
/**
|
|
* eeh_handle_event - Reset a PCI device after hard lockup.
|
|
* @pe: EEH PE
|
|
*
|
|
* While PHB detects address or data parity errors on particular PCI
|
|
* slot, the associated PE will be frozen. Besides, DMA's occurring
|
|
* to wild addresses (which usually happen due to bugs in device
|
|
* drivers or in PCI adapter firmware) can cause EEH error. #SERR,
|
|
* #PERR or other misc PCI-related errors also can trigger EEH errors.
|
|
*
|
|
* Recovery process consists of unplugging the device driver (which
|
|
* generated hotplug events to userspace), then issuing a PCI #RST to
|
|
* the device, then reconfiguring the PCI config space for all bridges
|
|
* & devices under this slot, and then finally restarting the device
|
|
* drivers (which cause a second set of hotplug events to go out to
|
|
* userspace).
|
|
*/
|
|
void eeh_handle_event(struct eeh_pe *pe)
|
|
{
|
|
if (pe)
|
|
eeh_handle_normal_event(pe);
|
|
else
|
|
eeh_handle_special_event();
|
|
}
|