PCI AER: software error injection
authorHuang Ying <ying.huang@intel.com>
Mon, 15 Jun 2009 02:42:57 +0000 (10:42 +0800)
committerJesse Barnes <jbarnes@virtuousgeek.org>
Tue, 16 Jun 2009 21:30:14 +0000 (14:30 -0700)
Debugging PCIE AER code can be very difficult because it is hard
to trigger various real hardware errors. This patch provide a
software based error injection tool, which can fake various PCIE
errors with a user space helper tool named "aer-inject". Which
can be gotten from:

  http://www.kernel.org/pub/linux/kernel/people/yhuang/

The patch fakes AER error by faking some PCIE AER related
registers and an AER interrupt for specified the PCIE device.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Documentation/PCI/pcieaer-howto.txt
drivers/pci/pcie/aer/Kconfig
drivers/pci/pcie/aer/Kconfig.debug [new file with mode: 0644]
drivers/pci/pcie/aer/Makefile
drivers/pci/pcie/aer/aer_inject.c [new file with mode: 0644]

index 5408b9b..be21001 100644 (file)
@@ -267,7 +267,7 @@ After reboot with new kernel or insert the module, a device file named
 
 Then, you need a user space tool named aer-inject, which can be gotten
 from:
-    http://www.kernel.org/pub/linux/kernel/people/yhuang/
+    http://www.kernel.org/pub/linux/utils/pci/aer-inject/
 
 More information about aer-inject can be found in the document comes
 with its source code.
index db4cb95..50e94e0 100644 (file)
@@ -23,3 +23,5 @@ config PCIE_ECRC
          (transaction layer end-to-end CRC checking).
 
          When in doubt, say N.
+
+source "drivers/pci/pcie/aer/Kconfig.debug"
diff --git a/drivers/pci/pcie/aer/Kconfig.debug b/drivers/pci/pcie/aer/Kconfig.debug
new file mode 100644 (file)
index 0000000..b8c925c
--- /dev/null
@@ -0,0 +1,18 @@
+#
+# PCI Express Root Port Device AER Debug Configuration
+#
+
+config PCIEAER_INJECT
+       tristate "PCIE AER error injector support"
+       depends on PCIEAER
+       default n
+       help
+         This enables PCI Express Root Port Advanced Error Reporting
+         (AER) software error injector.
+
+         Debuging PCIE AER code is quite difficult because it is hard
+         to trigger various real hardware errors. Software based
+         error injection can fake almost all kinds of errors with the
+         help of a user space helper tool aer-inject, which can be
+         gotten from:
+            http://www.kernel.org/pub/linux/utils/pci/aer-inject/
index 7f93411..2cba675 100644 (file)
@@ -9,3 +9,4 @@ obj-$(CONFIG_PCIE_ECRC) += ecrc.o
 aerdriver-objs := aerdrv_errprint.o aerdrv_core.o aerdrv.o
 aerdriver-$(CONFIG_ACPI) += aerdrv_acpi.o
 
+obj-$(CONFIG_PCIEAER_INJECT) += aer_inject.o
diff --git a/drivers/pci/pcie/aer/aer_inject.c b/drivers/pci/pcie/aer/aer_inject.c
new file mode 100644 (file)
index 0000000..d92ae21
--- /dev/null
@@ -0,0 +1,473 @@
+/*
+ * PCIE AER software error injection support.
+ *
+ * Debuging PCIE AER code is quite difficult because it is hard to
+ * trigger various real hardware errors. Software based error
+ * injection can fake almost all kinds of errors with the help of a
+ * user space helper tool aer-inject, which can be gotten from:
+ *   http://www.kernel.org/pub/linux/utils/pci/aer-inject/
+ *
+ * Copyright 2009 Intel Corporation.
+ *     Huang Ying <ying.huang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/pci.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+#include "aerdrv.h"
+
+struct aer_error_inj
+{
+       u8 bus;
+       u8 dev;
+       u8 fn;
+       u32 uncor_status;
+       u32 cor_status;
+       u32 header_log0;
+       u32 header_log1;
+       u32 header_log2;
+       u32 header_log3;
+};
+
+struct aer_error
+{
+       struct list_head list;
+       unsigned int bus;
+       unsigned int devfn;
+       int pos_cap_err;
+
+       u32 uncor_status;
+       u32 cor_status;
+       u32 header_log0;
+       u32 header_log1;
+       u32 header_log2;
+       u32 header_log3;
+       u32 root_status;
+       u32 source_id;
+};
+
+struct pci_bus_ops
+{
+       struct list_head list;
+       struct pci_bus *bus;
+       struct pci_ops *ops;
+};
+
+static LIST_HEAD(einjected);
+
+static LIST_HEAD(pci_bus_ops_list);
+
+/* Protect einjected and pci_bus_ops_list */
+static DEFINE_SPINLOCK(inject_lock);
+
+static void aer_error_init(struct aer_error *err, unsigned int bus,
+                          unsigned int devfn, int pos_cap_err)
+{
+       INIT_LIST_HEAD(&err->list);
+       err->bus = bus;
+       err->devfn = devfn;
+       err->pos_cap_err = pos_cap_err;
+}
+
+/* inject_lock must be held before calling */
+static struct aer_error *__find_aer_error(unsigned int bus, unsigned int devfn)
+{
+       struct aer_error *err;
+
+       list_for_each_entry(err, &einjected, list) {
+               if (bus == err->bus && devfn == err->devfn)
+                       return err;
+       }
+       return NULL;
+}
+
+/* inject_lock must be held before calling */
+static struct aer_error *__find_aer_error_by_dev(struct pci_dev *dev)
+{
+       return __find_aer_error(dev->bus->number, dev->devfn);
+}
+
+/* inject_lock must be held before calling */
+static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus)
+{
+       struct pci_bus_ops *bus_ops;
+
+       list_for_each_entry(bus_ops, &pci_bus_ops_list, list) {
+               if (bus_ops->bus == bus)
+                       return bus_ops->ops;
+       }
+       return NULL;
+}
+
+static struct pci_bus_ops *pci_bus_ops_pop(void)
+{
+       unsigned long flags;
+       struct pci_bus_ops *bus_ops = NULL;
+
+       spin_lock_irqsave(&inject_lock, flags);
+       if (list_empty(&pci_bus_ops_list))
+               bus_ops = NULL;
+       else {
+               struct list_head *lh = pci_bus_ops_list.next;
+               list_del(lh);
+               bus_ops = list_entry(lh, struct pci_bus_ops, list);
+       }
+       spin_unlock_irqrestore(&inject_lock, flags);
+       return bus_ops;
+}
+
+static u32 *find_pci_config_dword(struct aer_error *err, int where,
+                                 int *prw1cs)
+{
+       int rw1cs = 0;
+       u32 *target = NULL;
+
+       if (err->pos_cap_err == -1)
+               return NULL;
+
+       switch (where - err->pos_cap_err) {
+       case PCI_ERR_UNCOR_STATUS:
+               target = &err->uncor_status;
+               rw1cs = 1;
+               break;
+       case PCI_ERR_COR_STATUS:
+               target = &err->cor_status;
+               rw1cs = 1;
+               break;
+       case PCI_ERR_HEADER_LOG:
+               target = &err->header_log0;
+               break;
+       case PCI_ERR_HEADER_LOG+4:
+               target = &err->header_log1;
+               break;
+       case PCI_ERR_HEADER_LOG+8:
+               target = &err->header_log2;
+               break;
+       case PCI_ERR_HEADER_LOG+12:
+               target = &err->header_log3;
+               break;
+       case PCI_ERR_ROOT_STATUS:
+               target = &err->root_status;
+               rw1cs = 1;
+               break;
+       case PCI_ERR_ROOT_COR_SRC:
+               target = &err->source_id;
+               break;
+       }
+       if (prw1cs)
+               *prw1cs = rw1cs;
+       return target;
+}
+
+static int pci_read_aer(struct pci_bus *bus, unsigned int devfn, int where,
+                       int size, u32 *val)
+{
+       u32 *sim;
+       struct aer_error *err;
+       unsigned long flags;
+       struct pci_ops *ops;
+
+       spin_lock_irqsave(&inject_lock, flags);
+       if (size != sizeof(u32))
+               goto out;
+       err = __find_aer_error(bus->number, devfn);
+       if (!err)
+               goto out;
+
+       sim = find_pci_config_dword(err, where, NULL);
+       if (sim) {
+               *val = *sim;
+               spin_unlock_irqrestore(&inject_lock, flags);
+               return 0;
+       }
+out:
+       ops = __find_pci_bus_ops(bus);
+       spin_unlock_irqrestore(&inject_lock, flags);
+       return ops->read(bus, devfn, where, size, val);
+}
+
+int pci_write_aer(struct pci_bus *bus, unsigned int devfn, int where, int size,
+                 u32 val)
+{
+       u32 *sim;
+       struct aer_error *err;
+       unsigned long flags;
+       int rw1cs;
+       struct pci_ops *ops;
+
+       spin_lock_irqsave(&inject_lock, flags);
+       if (size != sizeof(u32))
+               goto out;
+       err = __find_aer_error(bus->number, devfn);
+       if (!err)
+               goto out;
+
+       sim = find_pci_config_dword(err, where, &rw1cs);
+       if (sim) {
+               if (rw1cs)
+                       *sim ^= val;
+               else
+                       *sim = val;
+               spin_unlock_irqrestore(&inject_lock, flags);
+               return 0;
+       }
+out:
+       ops = __find_pci_bus_ops(bus);
+       spin_unlock_irqrestore(&inject_lock, flags);
+       return ops->write(bus, devfn, where, size, val);
+}
+
+static struct pci_ops pci_ops_aer = {
+       .read = pci_read_aer,
+       .write = pci_write_aer,
+};
+
+static void pci_bus_ops_init(struct pci_bus_ops *bus_ops,
+                            struct pci_bus *bus,
+                            struct pci_ops *ops)
+{
+       INIT_LIST_HEAD(&bus_ops->list);
+       bus_ops->bus = bus;
+       bus_ops->ops = ops;
+}
+
+static int pci_bus_set_aer_ops(struct pci_bus *bus)
+{
+       struct pci_ops *ops;
+       struct pci_bus_ops *bus_ops;
+       unsigned long flags;
+
+       bus_ops = kmalloc(sizeof(*bus_ops), GFP_KERNEL);
+       if (!bus_ops)
+               return -ENOMEM;
+       ops = pci_bus_set_ops(bus, &pci_ops_aer);
+       spin_lock_irqsave(&inject_lock, flags);
+       if (ops == &pci_ops_aer)
+               goto out;
+       pci_bus_ops_init(bus_ops, bus, ops);
+       list_add(&bus_ops->list, &pci_bus_ops_list);
+       bus_ops = NULL;
+out:
+       spin_unlock_irqrestore(&inject_lock, flags);
+       if (bus_ops)
+               kfree(bus_ops);
+       return 0;
+}
+
+static struct pci_dev *pcie_find_root_port(struct pci_dev *dev)
+{
+       while (1) {
+               if (!dev->is_pcie)
+                       break;
+               if (dev->pcie_type == PCI_EXP_TYPE_ROOT_PORT)
+                       return dev;
+               if (!dev->bus->self)
+                       break;
+               dev = dev->bus->self;
+       }
+       return NULL;
+}
+
+static int find_aer_device_iter(struct device *device, void *data)
+{
+       struct pcie_device **result = data;
+       struct pcie_device *pcie_dev;
+
+       if (device->bus == &pcie_port_bus_type) {
+               pcie_dev = to_pcie_device(device);
+               if (pcie_dev->service & PCIE_PORT_SERVICE_AER) {
+                       *result = pcie_dev;
+                       return 1;
+               }
+       }
+       return 0;
+}
+
+static int find_aer_device(struct pci_dev *dev, struct pcie_device **result)
+{
+       return device_for_each_child(&dev->dev, result, find_aer_device_iter);
+}
+
+static int aer_inject(struct aer_error_inj *einj)
+{
+       struct aer_error *err, *rperr;
+       struct aer_error *err_alloc = NULL, *rperr_alloc = NULL;
+       struct pci_dev *dev, *rpdev;
+       struct pcie_device *edev;
+       unsigned long flags;
+       unsigned int devfn = PCI_DEVFN(einj->dev, einj->fn);
+       int pos_cap_err, rp_pos_cap_err;
+       u32 sever;
+       int ret = 0;
+
+       dev = pci_get_bus_and_slot(einj->bus, devfn);
+       if (!dev)
+               return -EINVAL;
+       rpdev = pcie_find_root_port(dev);
+       if (!rpdev) {
+               ret = -EINVAL;
+               goto out_put;
+       }
+
+       pos_cap_err = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
+       if (!pos_cap_err) {
+               ret = -EIO;
+               goto out_put;
+       }
+       pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_SEVER, &sever);
+
+       rp_pos_cap_err = pci_find_ext_capability(rpdev, PCI_EXT_CAP_ID_ERR);
+       if (!rp_pos_cap_err) {
+               ret = -EIO;
+               goto out_put;
+       }
+
+       err_alloc =  kzalloc(sizeof(struct aer_error), GFP_KERNEL);
+       if (!err_alloc) {
+               ret = -ENOMEM;
+               goto out_put;
+       }
+       rperr_alloc =  kzalloc(sizeof(struct aer_error), GFP_KERNEL);
+       if (!rperr_alloc) {
+               ret = -ENOMEM;
+               goto out_put;
+       }
+
+       spin_lock_irqsave(&inject_lock, flags);
+
+       err = __find_aer_error_by_dev(dev);
+       if (!err) {
+               err = err_alloc;
+               err_alloc = NULL;
+               aer_error_init(err, einj->bus, devfn, pos_cap_err);
+               list_add(&err->list, &einjected);
+       }
+       err->uncor_status |= einj->uncor_status;
+       err->cor_status |= einj->cor_status;
+       err->header_log0 = einj->header_log0;
+       err->header_log1 = einj->header_log1;
+       err->header_log2 = einj->header_log2;
+       err->header_log3 = einj->header_log3;
+
+       rperr = __find_aer_error_by_dev(rpdev);
+       if (!rperr) {
+               rperr = rperr_alloc;
+               rperr_alloc = NULL;
+               aer_error_init(rperr, rpdev->bus->number, rpdev->devfn,
+                              rp_pos_cap_err);
+               list_add(&rperr->list, &einjected);
+       }
+       if (einj->cor_status) {
+               if (rperr->root_status & PCI_ERR_ROOT_COR_RCV)
+                       rperr->root_status |= PCI_ERR_ROOT_MULTI_COR_RCV;
+               else
+                       rperr->root_status |= PCI_ERR_ROOT_COR_RCV;
+               rperr->source_id &= 0xffff0000;
+               rperr->source_id |= (einj->bus << 8) | devfn;
+       }
+       if (einj->uncor_status) {
+               if (rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV)
+                       rperr->root_status |= PCI_ERR_ROOT_MULTI_UNCOR_RCV;
+               if (sever & einj->uncor_status) {
+                       rperr->root_status |= PCI_ERR_ROOT_FATAL_RCV;
+                       if (!(rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV))
+                               rperr->root_status |= PCI_ERR_ROOT_FIRST_FATAL;
+               } else
+                       rperr->root_status |= PCI_ERR_ROOT_NONFATAL_RCV;
+               rperr->root_status |= PCI_ERR_ROOT_UNCOR_RCV;
+               rperr->source_id &= 0x0000ffff;
+               rperr->source_id |= ((einj->bus << 8) | devfn) << 16;
+       }
+       spin_unlock_irqrestore(&inject_lock, flags);
+
+       ret = pci_bus_set_aer_ops(dev->bus);
+       if (ret)
+               goto out_put;
+       ret = pci_bus_set_aer_ops(rpdev->bus);
+       if (ret)
+               goto out_put;
+
+       if (find_aer_device(rpdev, &edev))
+               aer_irq(-1, edev);
+       else
+               ret = -EINVAL;
+out_put:
+       if (err_alloc)
+               kfree(err_alloc);
+       if (rperr_alloc)
+               kfree(rperr_alloc);
+       pci_dev_put(dev);
+       return ret;
+}
+
+static ssize_t aer_inject_write(struct file *filp, const char __user *ubuf,
+                               size_t usize, loff_t *off)
+{
+       struct aer_error_inj einj;
+       int ret;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       if (usize != sizeof(struct aer_error_inj))
+               return -EINVAL;
+
+       if (copy_from_user(&einj, ubuf, usize))
+               return -EFAULT;
+
+       ret = aer_inject(&einj);
+       return ret ? ret : usize;
+}
+
+static const struct file_operations aer_inject_fops = {
+       .write = aer_inject_write,
+       .owner = THIS_MODULE,
+};
+
+static struct miscdevice aer_inject_device = {
+       .minor = MISC_DYNAMIC_MINOR,
+       .name = "aer_inject",
+       .fops = &aer_inject_fops,
+};
+
+static int __init aer_inject_init(void)
+{
+       return misc_register(&aer_inject_device);
+}
+
+static void __exit aer_inject_exit(void)
+{
+       struct aer_error *err, *err_next;
+       unsigned long flags;
+       struct pci_bus_ops *bus_ops;
+
+       misc_deregister(&aer_inject_device);
+
+       while ((bus_ops = pci_bus_ops_pop())) {
+               pci_bus_set_ops(bus_ops->bus, bus_ops->ops);
+               kfree(bus_ops);
+       }
+
+       spin_lock_irqsave(&inject_lock, flags);
+       list_for_each_entry_safe(err, err_next,
+                                &pci_bus_ops_list, list) {
+               list_del(&err->list);
+               kfree(err);
+       }
+       spin_unlock_irqrestore(&inject_lock, flags);
+}
+
+module_init(aer_inject_init);
+module_exit(aer_inject_exit);
+
+MODULE_DESCRIPTION("PCIE AER software error injector");
+MODULE_LICENSE("GPL");