Re: [PATCH 3/4] PCI: PCIE AER: PCIE AER software error injection

From: Huang Ying
Date: Sun Jun 14 2009 - 22:43:25 EST


On Fri, 2009-06-12 at 23:53 +0800, Barnes, Jesse wrote:
> On Thu, 11 Jun 2009 18:54:01 -0700
> "Huang, Ying" <ying.huang@xxxxxxxxx> wrote:
>
> > On Fri, 2009-06-12 at 02:59 +0800, Barnes, Jesse wrote:
> > > On Fri, 24 Apr 2009 10:45:27 +0800
> > > Huang Ying <ying.huang@xxxxxxxxx> wrote:
> > >
> > > > 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@xxxxxxxxx>
> > > >
> > >
> > > This patch got mangled, care to resend?
> >
> > Sorry. Resend patch follows.
> >
>
> This one didn't apply either; can you pull down my linux-next branch
> and diff against that? Also, cc my personal address,
> jbarnes@xxxxxxxxxxxxxxxx, so Exchange doesn't mess up the patch.

Re-base on
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6.git branch
linux-next.

Sent as attachment, I think that works even for Exchange.

Another patch to fix the user space tool URL is attached with the mail
too. Please fold it into inject document patch if possible.

Best Regards,
Huang Ying

From: Huang Ying <ying.huang@xxxxxxxxx>
Subject: pci: Fix user space tool URL in PCIE AER document

The user space tool URL in PCIE AER document has been changed, so fix it.

Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>

---
Documentation/PCI/pcieaer-howto.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/Documentation/PCI/pcieaer-howto.txt
+++ b/Documentation/PCI/pcieaer-howto.txt
@@ -263,7 +263,7 @@ After reboot with new kernel or insert t

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.
From: Huang Ying <ying.huang@xxxxxxxxx>
Subject: pci: PCIE AER software error injection

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/utils/pci/aer-inject/

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@xxxxxxxxx>

---
drivers/pci/pcie/aer/Kconfig | 2
drivers/pci/pcie/aer/Kconfig.debug | 18 +
drivers/pci/pcie/aer/Makefile | 1
drivers/pci/pcie/aer/aer_inject.c | 473 +++++++++++++++++++++++++++++++++++++
4 files changed, 494 insertions(+)

--- /dev/null
+++ b/drivers/pci/pcie/aer/aer_inject.c
@@ -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@xxxxxxxxx>
+ *
+ * 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");
--- a/drivers/pci/pcie/aer/Kconfig
+++ b/drivers/pci/pcie/aer/Kconfig
@@ -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"
--- a/drivers/pci/pcie/aer/Makefile
+++ b/drivers/pci/pcie/aer/Makefile
@@ -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
--- /dev/null
+++ b/drivers/pci/pcie/aer/Kconfig.debug
@@ -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/