[RFC 1/3] powerpc/eeh: Synchronization for safety
Ganesh Goudar
ganeshgr at linux.ibm.com
Tue Aug 16 13:27:14 AEST 2022
Based on the original work from Sam Bobroff.
There is currently little synchronization between EEH error detection
(eeh_dev_check_failure()), EEH error recovery
(eeh_handle_{normal,special}_event()) and the PCI subsystem (device
addition and removal), and so there are race conditions that lead to
crashes (often access to free'd memory or LIST_POISON).
However, a solution must consider:
- EEH error detection can occur in interrupt context, which prevents
the use of a mutex.
- EEH recovery may need to sleep, which prevents the use of a spinlock.
- EEH recovery uses PCI operations that may require the PCI
rescan/remove lock and/or device lock to be held
- PCI operations may hold the rescan/remove and/or device lock when
calling into EEH functions.
- Device driver callbacks may perform arbitrary PCI operations
during recovery, including device removal.
In this patch the existing mutex and spinlock are combined with the
EEH_PE_RECOVERING flag to provide some assurances that are then used
to reduce the race conditions.
The fields to be protected are the ones that provide the structure
of the trees of struct eeh_pe that are held for each PHB: the parent
pointer and child lists and the list of struct eeh_dev, as well as
the pe and pdev pointers within struct eeh_dev.
The existing way of using EEH_PE_RECOVERING is kept and slightly
extended: No struct eeh_pe will be removed while it has the flag set
on it. Additionally, when adding new PEs, they are marked
EEH_PE_RECOVERING if their parent PE is marked: this allows the
recovery thread to assume that all PEs underneath the one it's
processing will continue to exist during recovery.
Both the mutex and spinlock are held while any protected field is
changed or a PE is deleted, so holding either of them (elsewhere) will
keep them stable and safe to access. Additionally, if
EEH_PE_RECOVERING is set on a PE then the locks can be released and
re-acquired safely, as long as the protected fields aren't used while
no locks are held. This is used during recovery to release locks
for long sleeps (i.e. during eeh_wait_state() when we may sleep up to
5 minutes), or to maintain lock ordering.
The spinlock is used in error detection (which cannot use a mutex, see
above) and also where it's possible that the mutex is already held.
The mutex is used in areas that don't have that restriction, and where
blocking may be required. Care must be taken when ordering these locks
against the PCI rescan/remove lock and the device locks to avoid
deadlocking.
Signed-off-by: Ganesh Goudar <ganeshgr at linux.ibm.com>
---
arch/powerpc/include/asm/eeh.h | 6 +-
arch/powerpc/kernel/eeh.c | 112 ++++++--
arch/powerpc/kernel/eeh_driver.c | 287 ++++++++++++++-----
arch/powerpc/kernel/eeh_pe.c | 30 +-
arch/powerpc/platforms/powernv/eeh-powernv.c | 12 +-
arch/powerpc/platforms/pseries/eeh_pseries.c | 5 +-
arch/powerpc/platforms/pseries/pci_dlpar.c | 5 +-
drivers/pci/hotplug/pnv_php.c | 5 +-
drivers/pci/hotplug/rpadlpar_core.c | 2 +
drivers/vfio/vfio_spapr_eeh.c | 10 +-
10 files changed, 364 insertions(+), 110 deletions(-)
diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 514dd056c2c8..f659c0433de5 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -271,11 +271,15 @@ static inline bool eeh_state_active(int state)
== (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE);
}
+void eeh_recovery_lock(void);
+void eeh_recovery_unlock(void);
+void eeh_recovery_must_be_locked(void);
+
typedef void (*eeh_edev_traverse_func)(struct eeh_dev *edev, void *flag);
typedef void *(*eeh_pe_traverse_func)(struct eeh_pe *pe, void *flag);
void eeh_set_pe_aux_size(int size);
int eeh_phb_pe_create(struct pci_controller *phb);
-int eeh_wait_state(struct eeh_pe *pe, int max_wait);
+int eeh_wait_state(struct eeh_pe *pe, int max_waiti, bool unlock);
struct eeh_pe *eeh_phb_pe_get(struct pci_controller *phb);
struct eeh_pe *eeh_pe_next(struct eeh_pe *pe, struct eeh_pe *root);
struct eeh_pe *eeh_pe_get(struct pci_controller *phb, int pe_no);
diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index ab316e155ea9..2c90c37524ed 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -108,7 +108,25 @@ bool eeh_debugfs_no_recover;
/* Platform dependent EEH operations */
struct eeh_ops *eeh_ops = NULL;
-/* Lock to avoid races due to multiple reports of an error */
+/*
+ * confirm_error_lock and eeh_dev_mutex are used together to provide
+ * safety during EEH operations.
+ *
+ * Generally, the spinlock is used in error detection where it's not possible
+ * to use a mutex or where there is potential to deadlock with the mutex, and
+ * the mutex is used during recovery and other PCI related operations. One must
+ * be held when reading and both must be held when making changes to the
+ * protected fields: eeh_pe.parent, child_list, child, edevs and eeh_dev.pe,
+ * .pdev.
+ *
+ * Lock ordering:
+ * - the PCI rescan/remove mutex (see pci_lock_rescan_remove())
+ * - the struct device lock (see device_lock())
+ * - the eeh_dev_mutex mutex (see eeh_recovery_lock())
+ * - the confirm_error_lock spinlock (see eeh_serialize_lock())
+ * - the eeh_eventlist_lock spinlock
+ */
+
DEFINE_RAW_SPINLOCK(confirm_error_lock);
EXPORT_SYMBOL_GPL(confirm_error_lock);
@@ -160,6 +178,23 @@ void eeh_show_enabled(void)
pr_info("EEH: No capable adapters found: recovery disabled.\n");
}
+void eeh_recovery_lock(void)
+{
+ mutex_lock(&eeh_dev_mutex);
+}
+EXPORT_SYMBOL_GPL(eeh_recovery_lock);
+
+void eeh_recovery_unlock(void)
+{
+ mutex_unlock(&eeh_dev_mutex);
+}
+EXPORT_SYMBOL_GPL(eeh_recovery_unlock);
+void eeh_recovery_must_be_locked(void)
+{
+ WARN_ON_ONCE(!mutex_is_locked(&eeh_dev_mutex));
+}
+EXPORT_SYMBOL_GPL(eeh_recovery_must_be_locked);
+
/*
* This routine captures assorted PCI configuration space data
* for the indicated PCI device, and puts them into a buffer
@@ -353,11 +388,12 @@ static inline unsigned long eeh_token_to_phys(unsigned long token)
* On PowerNV platform, we might already have fenced PHB there.
* For that case, it's meaningless to recover frozen PE. Intead,
* We have to handle fenced PHB firstly.
+ *
+ * eeh_serialize_lock must be held when calling this function.
*/
static int eeh_phb_check_failure(struct eeh_pe *pe)
{
struct eeh_pe *phb_pe;
- unsigned long flags;
int ret;
if (!eeh_has_flag(EEH_PROBE_MODE_DEV))
@@ -372,7 +408,6 @@ static int eeh_phb_check_failure(struct eeh_pe *pe)
}
/* If the PHB has been in problematic state */
- eeh_serialize_lock(&flags);
if (phb_pe->state & EEH_PE_ISOLATED) {
ret = 0;
goto out;
@@ -388,14 +423,12 @@ static int eeh_phb_check_failure(struct eeh_pe *pe)
/* Isolate the PHB and send event */
eeh_pe_mark_isolated(phb_pe);
- eeh_serialize_unlock(flags);
pr_debug("EEH: PHB#%x failure detected, location: %s\n",
phb_pe->phb->global_number, eeh_pe_loc_get(phb_pe));
eeh_send_failure_event(phb_pe);
return 1;
out:
- eeh_serialize_unlock(flags);
return ret;
}
@@ -423,12 +456,11 @@ static inline const char *eeh_driver_name(struct pci_dev *pdev)
*/
int eeh_dev_check_failure(struct eeh_dev *edev)
{
- int ret;
unsigned long flags;
struct device_node *dn;
struct pci_dev *dev;
struct eeh_pe *pe, *parent_pe;
- int rc = 0;
+ int rc;
const char *location = NULL;
eeh_stats.total_mmio_ffs++;
@@ -440,6 +472,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
eeh_stats.no_dn++;
return 0;
}
+ eeh_serialize_lock(&flags);
dev = eeh_dev_to_pci_dev(edev);
pe = eeh_dev_to_pe(edev);
@@ -447,24 +480,27 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
if (!pe) {
eeh_stats.ignored_check++;
eeh_edev_dbg(edev, "Ignored check\n");
- return 0;
+ rc = 0;
+ goto dn_unlock;
}
/*
* On PowerNV platform, we might already have fenced PHB
* there and we need take care of that firstly.
*/
- ret = eeh_phb_check_failure(pe);
- if (ret > 0)
- return ret;
+ rc = eeh_phb_check_failure(pe);
+ if (rc > 0)
+ goto dn_unlock;
/*
* If the PE isn't owned by us, we shouldn't check the
* state. Instead, let the owner handle it if the PE has
* been frozen.
*/
- if (eeh_pe_passed(pe))
- return 0;
+ if (eeh_pe_passed(pe)) {
+ rc = 0;
+ goto dn_unlock;
+ }
/* If we already have a pending isolation event for this
* slot, we know it's bad already, we don't need to check.
@@ -472,8 +508,6 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
* in one slot might report errors simultaneously, and we
* only want one error recovery routine running.
*/
- eeh_serialize_lock(&flags);
- rc = 1;
if (pe->state & EEH_PE_ISOLATED) {
pe->check_count++;
if (pe->check_count == EEH_MAX_FAILS) {
@@ -489,6 +523,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
eeh_driver_name(dev));
dump_stack();
}
+ rc = 1;
goto dn_unlock;
}
@@ -499,7 +534,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
* function zero of a multi-function device.
* In any case they must share a common PHB.
*/
- ret = eeh_ops->get_state(pe, NULL);
+ rc = eeh_ops->get_state(pe, NULL);
/* Note that config-io to empty slots may fail;
* they are empty when they don't have children.
@@ -507,8 +542,8 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
* PE's state, EEH not support and Permanently unavailable
* state, PE is in good state.
*/
- if ((ret < 0) ||
- (ret == EEH_STATE_NOT_SUPPORT) || eeh_state_active(ret)) {
+ if (rc < 0 ||
+ rc == EEH_STATE_NOT_SUPPORT || eeh_state_active(rc)) {
eeh_stats.false_positives++;
pe->false_positives++;
rc = 0;
@@ -527,8 +562,8 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
break;
/* Frozen parent PE ? */
- ret = eeh_ops->get_state(parent_pe, NULL);
- if (ret > 0 && !eeh_state_active(ret)) {
+ rc = eeh_ops->get_state(parent_pe, NULL);
+ if (rc > 0 && !eeh_state_active(rc)) {
pe = parent_pe;
pr_err("EEH: Failure of PHB#%x-PE#%x will be handled at parent PHB#%x-PE#%x.\n",
pe->phb->global_number, pe->addr,
@@ -546,7 +581,6 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
* bridges.
*/
eeh_pe_mark_isolated(pe);
- eeh_serialize_unlock(flags);
/* Most EEH events are due to device driver bugs. Having
* a stack trace will help the device-driver authors figure
@@ -555,6 +589,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev)
pr_debug("EEH: %s: Frozen PHB#%x-PE#%x detected\n",
__func__, pe->phb->global_number, pe->addr);
eeh_send_failure_event(pe);
+ eeh_serialize_unlock(flags);
return 1;
@@ -659,7 +694,7 @@ int eeh_pci_enable(struct eeh_pe *pe, int function)
/* Check if the request is finished successfully */
if (active_flag) {
- rc = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC);
+ rc = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC, false);
if (rc < 0)
return rc;
@@ -857,7 +892,7 @@ int eeh_pe_reset_full(struct eeh_pe *pe, bool include_passed)
pe->phb->global_number, pe->addr, i + 1);
/* Wait until the PE is in a functioning state */
- state = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC);
+ state = eeh_wait_state(pe, PCI_BUS_RESET_WAIT_MSEC, false);
if (state < 0) {
pr_warn("EEH: Unrecoverable slot failure on PHB#%x-PE#%x",
pe->phb->global_number, pe->addr);
@@ -933,7 +968,9 @@ static int eeh_device_notifier(struct notifier_block *nb,
* the device's resources, which have not yet been set up.
*/
case BUS_NOTIFY_DEL_DEVICE:
+ eeh_recovery_lock();
eeh_remove_device(to_pci_dev(dev));
+ eeh_recovery_unlock();
break;
default:
break;
@@ -998,6 +1035,7 @@ int eeh_init(struct eeh_ops *ops)
void eeh_probe_device(struct pci_dev *dev)
{
struct eeh_dev *edev;
+ unsigned long flags;
pr_debug("EEH: Adding device %s\n", pci_name(dev));
@@ -1038,9 +1076,13 @@ void eeh_probe_device(struct pci_dev *dev)
edev->mode |= EEH_DEV_NO_HANDLER;
}
+ /* Both locks are required to make changes */
+ eeh_recovery_must_be_locked();
+ eeh_serialize_lock(&flags);
/* bind the pdev and the edev together */
edev->pdev = dev;
dev->dev.archdata.edev = edev;
+ eeh_serialize_unlock(flags);
eeh_addr_cache_insert_dev(dev);
eeh_sysfs_add_device(dev);
}
@@ -1058,6 +1100,7 @@ void eeh_probe_device(struct pci_dev *dev)
void eeh_remove_device(struct pci_dev *dev)
{
struct eeh_dev *edev;
+ unsigned long flags;
if (!dev || !eeh_enabled())
return;
@@ -1071,6 +1114,9 @@ void eeh_remove_device(struct pci_dev *dev)
return;
}
+ /* Both locks are required to make changes */
+ eeh_recovery_must_be_locked();
+ eeh_serialize_lock(&flags);
/*
* During the hotplug for EEH error recovery, we need the EEH
* device attached to the parent PE in order for BAR restore
@@ -1078,6 +1124,7 @@ void eeh_remove_device(struct pci_dev *dev)
* from the parent PE during the BAR resotre.
*/
edev->pdev = NULL;
+ eeh_serialize_unlock(flags);
/*
* eeh_sysfs_remove_device() uses pci_dev_to_eeh_dev() so we need to
@@ -1103,7 +1150,11 @@ void eeh_remove_device(struct pci_dev *dev)
* for the VF EEH device.
*/
edev->in_error = false;
+ /* Both locks are required to make changes */
+ eeh_recovery_must_be_locked();
+ eeh_serialize_lock(&flags);
dev->dev.archdata.edev = NULL;
+ eeh_serialize_unlock(flags);
if (!(edev->pe->state & EEH_PE_KEEP))
eeh_pe_tree_remove(edev);
else
@@ -1199,7 +1250,7 @@ int eeh_dev_open(struct pci_dev *pdev)
struct eeh_dev *edev;
int ret = -ENODEV;
- mutex_lock(&eeh_dev_mutex);
+ eeh_recovery_lock();
/* No PCI device ? */
if (!pdev)
@@ -1222,11 +1273,11 @@ int eeh_dev_open(struct pci_dev *pdev)
/* Increase PE's pass through count */
atomic_inc(&edev->pe->pass_dev_cnt);
- mutex_unlock(&eeh_dev_mutex);
+ eeh_recovery_unlock();
return 0;
out:
- mutex_unlock(&eeh_dev_mutex);
+ eeh_recovery_unlock();
return ret;
}
EXPORT_SYMBOL_GPL(eeh_dev_open);
@@ -1243,7 +1294,7 @@ void eeh_dev_release(struct pci_dev *pdev)
{
struct eeh_dev *edev;
- mutex_lock(&eeh_dev_mutex);
+ eeh_recovery_lock();
/* No PCI device ? */
if (!pdev)
@@ -1258,7 +1309,7 @@ void eeh_dev_release(struct pci_dev *pdev)
WARN_ON(atomic_dec_if_positive(&edev->pe->pass_dev_cnt) < 0);
eeh_pe_change_owner(edev->pe);
out:
- mutex_unlock(&eeh_dev_mutex);
+ eeh_recovery_unlock();
}
EXPORT_SYMBOL(eeh_dev_release);
@@ -1646,6 +1697,7 @@ static ssize_t eeh_force_recover_write(struct file *filp,
struct eeh_pe *pe;
char buf[20];
int ret;
+ unsigned long flags;
ret = simple_write_to_buffer(buf, sizeof(buf), ppos, user_buf, count);
if (!ret)
@@ -1658,7 +1710,9 @@ static ssize_t eeh_force_recover_write(struct file *filp,
* recoveries can occur.
*/
if (!strncmp(buf, "hwcheck", 7)) {
+ eeh_serialize_lock(&flags);
__eeh_send_failure_event(NULL);
+ eeh_serialize_unlock(flags);
return count;
}
@@ -1682,7 +1736,9 @@ static ssize_t eeh_force_recover_write(struct file *filp,
* from an odd state (e.g. PE removed, or recovery of a
* non-isolated PE)
*/
+ eeh_serialize_lock(&flags);
__eeh_send_failure_event(pe);
+ eeh_serialize_unlock(flags);
return ret < 0 ? ret : count;
}
diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c
index 260273e56431..d956ae624691 100644
--- a/arch/powerpc/kernel/eeh_driver.c
+++ b/arch/powerpc/kernel/eeh_driver.c
@@ -247,65 +247,124 @@ static void eeh_set_irq_state(struct eeh_pe *root, bool enable)
}
}
-typedef enum pci_ers_result (*eeh_report_fn)(struct eeh_dev *,
- struct pci_dev *,
+typedef enum pci_ers_result (*eeh_report_fn)(struct pci_dev *,
struct pci_driver *);
-static void eeh_pe_report_edev(struct eeh_dev *edev, eeh_report_fn fn,
+static void eeh_pe_report_pdev(struct pci_dev *pdev, eeh_report_fn fn,
enum pci_ers_result *result)
{
- struct pci_dev *pdev;
+ struct eeh_dev *edev;
struct pci_driver *driver;
+ bool actionable, late, removed, passed;
enum pci_ers_result new_result;
- pci_lock_rescan_remove();
- pdev = edev->pdev;
- if (pdev)
- get_device(&pdev->dev);
- pci_unlock_rescan_remove();
- if (!pdev) {
- eeh_edev_info(edev, "no device");
+ edev = pci_dev_to_eeh_dev(pdev);
+ if (!edev) {
+ pci_info(pdev, "no EEH state for device");
return;
}
- device_lock(&pdev->dev);
- if (eeh_edev_actionable(edev)) {
+ /* Cache some useful values before releasing the lock: */
+ actionable = eeh_edev_actionable(edev);
+ late = edev->mode & EEH_DEV_NO_HANDLER;
+ removed = eeh_dev_removed(edev);
+ passed = eeh_pe_passed(edev->pe);
+ if (actionable) {
+ /*
+ * Driver callbacks may end up calling back into EEH functions
+ * (for example by removing a PCI device) which will deadlock
+ * unless the EEH locks are released first. Note that it may be
+ * re-acquired by the report functions, if necessary.
+ */
+ eeh_recovery_unlock();
+ device_lock(&pdev->dev);
driver = eeh_pcid_get(pdev);
if (!driver)
- eeh_edev_info(edev, "no driver");
+ pci_info(pdev, "no driver");
else if (!driver->err_handler)
- eeh_edev_info(edev, "driver not EEH aware");
- else if (edev->mode & EEH_DEV_NO_HANDLER)
- eeh_edev_info(edev, "driver bound too late");
+ pci_info(pdev, "driver not EEH aware");
+ else if (late)
+ pci_info(pdev, "driver bound too late");
else {
- new_result = fn(edev, pdev, driver);
- eeh_edev_info(edev, "%s driver reports: '%s'",
- driver->name,
- pci_ers_result_name(new_result));
+ new_result = fn(pdev, driver);
+ /*
+ * It's not safe to use edev here, because the locks
+ * have been released and devices could have changed.
+ */
+ pci_info(pdev, "%s driver reports: '%s'",
+ driver->name,
+ pci_ers_result_name(new_result));
if (result)
*result = pci_ers_merge_result(*result,
new_result);
}
if (driver)
eeh_pcid_put(pdev);
+ device_unlock(&pdev->dev);
+ eeh_recovery_lock();
} else {
- eeh_edev_info(edev, "not actionable (%d,%d,%d)", !!pdev,
- !eeh_dev_removed(edev), !eeh_pe_passed(edev->pe));
+ pci_info(pdev, "not actionable (%d,%d,%d)", !!pdev,
+ !removed, !passed);
}
- device_unlock(&pdev->dev);
- if (edev->pdev != pdev)
- eeh_edev_warn(edev, "Device changed during processing!\n");
- put_device(&pdev->dev);
}
-static void eeh_pe_report(const char *name, struct eeh_pe *root,
- eeh_report_fn fn, enum pci_ers_result *result)
+struct pci_dev **pdev_cache_list_create(struct eeh_pe *root)
{
struct eeh_pe *pe;
struct eeh_dev *edev, *tmp;
+ struct pci_dev **pdevs;
+ int i, n;
+
+ n = 0;
+ eeh_for_each_pe(root, pe) eeh_pe_for_each_dev(pe, edev, tmp) {
+ if (edev->pdev)
+ n++;
+ }
+ pdevs = kmalloc(sizeof(*pdevs) * (n + 1), GFP_KERNEL);
+ if (WARN_ON_ONCE(!pdevs))
+ return NULL;
+ i = 0;
+ eeh_for_each_pe(root, pe) eeh_pe_for_each_dev(pe, edev, tmp) {
+ if (i < n) {
+ get_device(&edev->pdev->dev);
+ pdevs[i++] = edev->pdev;
+ }
+ }
+ if (WARN_ON_ONCE(i < n))
+ n = i;
+ pdevs[n] = NULL; /* terminator */
+ return pdevs;
+}
+
+static void pdev_cache_list_destroy(struct pci_dev **pdevs)
+{
+ struct pci_dev **pdevp;
+
+ for (pdevp = pdevs; pdevp && *pdevp; pdevp++)
+ put_device(&(*pdevp)->dev);
+ kfree(pdevs);
+}
+
+static void eeh_pe_report(const char *name, struct eeh_pe *root,
+ eeh_report_fn fn, enum pci_ers_result *result)
+{
+ struct pci_dev **pdevs, **pdevp;
pr_info("EEH: Beginning: '%s'\n", name);
- eeh_for_each_pe(root, pe) eeh_pe_for_each_dev(pe, edev, tmp)
- eeh_pe_report_edev(edev, fn, result);
+ /*
+ * It would be convenient to continue to hold the recovery lock here
+ * but driver callbacks can take a very long time or never return at
+ * all.
+ */
+ pdevs = pdev_cache_list_create(root);
+ for (pdevp = pdevs; pdevp && *pdevp; pdevp++) {
+ /*
+ * NOTE! eeh_recovery_lock() is released briefly
+ * in eeh_pe_report_pdev()
+ */
+ eeh_pe_report_pdev(*pdevp, fn, result);
+ }
+ pdev_cache_list_destroy(pdevs);
+
if (result)
pr_info("EEH: Finished:'%s' with aggregate recovery state:'%s'\n",
name, pci_ers_result_name(*result));
@@ -315,25 +374,30 @@ static void eeh_pe_report(const char *name, struct eeh_pe *root,
/**
* eeh_report_error - Report pci error to each device driver
- * @edev: eeh device
+ * @pdev: eeh device
* @driver: device's PCI driver
*
* Report an EEH error to each device driver.
*/
-static enum pci_ers_result eeh_report_error(struct eeh_dev *edev,
- struct pci_dev *pdev,
+static enum pci_ers_result eeh_report_error(struct pci_dev *pdev,
struct pci_driver *driver)
{
enum pci_ers_result rc;
+ struct eeh_dev *edev;
+ unsigned long flags;
if (!driver->err_handler->error_detected)
return PCI_ERS_RESULT_NONE;
- eeh_edev_info(edev, "Invoking %s->error_detected(IO frozen)",
- driver->name);
+ pci_info(pdev, "Invoking %s->error_detected(IO frozen)", driver->name);
rc = driver->err_handler->error_detected(pdev, pci_channel_io_frozen);
- edev->in_error = true;
+ eeh_serialize_lock(&flags);
+ edev = pci_dev_to_eeh_dev(pdev);
+ if (edev)
+ edev->in_error = true;
+ eeh_serialize_unlock(flags);
+
pci_uevent_ers(pdev, PCI_ERS_RESULT_NONE);
return rc;
}
@@ -346,19 +410,19 @@ static enum pci_ers_result eeh_report_error(struct eeh_dev *edev,
* Tells each device driver that IO ports, MMIO and config space I/O
* are now enabled.
*/
-static enum pci_ers_result eeh_report_mmio_enabled(struct eeh_dev *edev,
- struct pci_dev *pdev,
+static enum pci_ers_result eeh_report_mmio_enabled(struct pci_dev *pdev,
struct pci_driver *driver)
{
if (!driver->err_handler->mmio_enabled)
return PCI_ERS_RESULT_NONE;
- eeh_edev_info(edev, "Invoking %s->mmio_enabled()", driver->name);
+ pci_info(pdev, "Invoking %s->mmio_enabled()", driver->name);
return driver->err_handler->mmio_enabled(pdev);
}
/**
* eeh_report_reset - Tell device that slot has been reset
* @edev: eeh device
+ * @edev: eeh device
* @driver: device's PCI driver
*
* This routine must be called while EEH tries to reset particular
@@ -366,13 +430,20 @@ static enum pci_ers_result eeh_report_mmio_enabled(struct eeh_dev *edev,
* some actions, usually to save data the driver needs so that the
* driver can work again while the device is recovered.
*/
-static enum pci_ers_result eeh_report_reset(struct eeh_dev *edev,
- struct pci_dev *pdev,
+static enum pci_ers_result eeh_report_reset(struct pci_dev *pdev,
struct pci_driver *driver)
{
- if (!driver->err_handler->slot_reset || !edev->in_error)
+ struct eeh_dev *edev;
+ unsigned long flags;
+
+ eeh_serialize_lock(&flags);
+ edev = pci_dev_to_eeh_dev(pdev);
+ if (!driver->err_handler->slot_reset || !edev->in_error) {
+ eeh_serialize_unlock(flags);
return PCI_ERS_RESULT_NONE;
- eeh_edev_info(edev, "Invoking %s->slot_reset()", driver->name);
+ }
+ eeh_serialize_unlock(flags);
+ pci_info(pdev, "Invoking %s->slot_reset()", driver->name);
return driver->err_handler->slot_reset(pdev);
}
@@ -412,20 +483,29 @@ static void eeh_dev_restore_state(struct eeh_dev *edev, void *userdata)
* could resume so that the device driver can do some initialization
* to make the recovered device work again.
*/
-static enum pci_ers_result eeh_report_resume(struct eeh_dev *edev,
- struct pci_dev *pdev,
+static enum pci_ers_result eeh_report_resume(struct pci_dev *pdev,
struct pci_driver *driver)
{
- if (!driver->err_handler->resume || !edev->in_error)
+ struct eeh_dev *edev;
+ unsigned long flags;
+
+ eeh_serialize_lock(&flags);
+ edev = pci_dev_to_eeh_dev(pdev);
+ if (!driver->err_handler->resume || !edev->in_error) {
+ eeh_serialize_unlock(flags);
return PCI_ERS_RESULT_NONE;
+ }
+ eeh_serialize_unlock(flags);
- eeh_edev_info(edev, "Invoking %s->resume()", driver->name);
+ pci_info(pdev, "Invoking %s->resume()", driver->name);
driver->err_handler->resume(pdev);
- pci_uevent_ers(edev->pdev, PCI_ERS_RESULT_RECOVERED);
+ pci_uevent_ers(pdev, PCI_ERS_RESULT_RECOVERED);
#ifdef CONFIG_PCI_IOV
+ eeh_serialize_lock(&flags);
if (eeh_ops->notify_resume)
eeh_ops->notify_resume(edev);
+ eeh_serialize_unlock(flags);
#endif
return PCI_ERS_RESULT_NONE;
}
@@ -438,8 +518,7 @@ static enum pci_ers_result eeh_report_resume(struct eeh_dev *edev,
* This informs the device driver that the device is permanently
* dead, and that no further recovery attempts will be made on it.
*/
-static enum pci_ers_result eeh_report_failure(struct eeh_dev *edev,
- struct pci_dev *pdev,
+static enum pci_ers_result eeh_report_failure(struct pci_dev *pdev,
struct pci_driver *driver)
{
enum pci_ers_result rc;
@@ -447,8 +526,8 @@ static enum pci_ers_result eeh_report_failure(struct eeh_dev *edev,
if (!driver->err_handler->error_detected)
return PCI_ERS_RESULT_NONE;
- eeh_edev_info(edev, "Invoking %s->error_detected(permanent failure)",
- driver->name);
+ pci_info(pdev, "Invoking %s->error_detected(permanent failure)",
+ driver->name);
rc = driver->err_handler->error_detected(pdev,
pci_channel_io_perm_failure);
@@ -476,17 +555,38 @@ static void *eeh_add_virt_device(struct eeh_dev *edev)
}
#ifdef CONFIG_PCI_IOV
- pci_iov_add_virtfn(edev->physfn, edev->vf_index);
+ {
+ struct pci_dev *physfn = edev->physfn;
+ int vf_index = eeh_dev_to_pdn(edev)->vf_index;
+
+ get_device(&physfn->dev);
+ eeh_recovery_unlock();
+ /*
+ * This PCI operation will call back into EEH code where the
+ * recovery lock will be acquired, so it must be released here,
+ * first:
+ */
+ pci_iov_add_virtfn(physfn, vf_index);
+ put_device(&physfn->dev);
+ eeh_recovery_lock();
+ }
#endif
return NULL;
}
-static void eeh_rmv_device(struct eeh_dev *edev, void *userdata)
+static void eeh_rmv_device(struct pci_dev *pdev, void *userdata)
{
+ struct eeh_dev *edev;
struct pci_driver *driver;
- struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
struct eeh_rmv_data *rmv_data = (struct eeh_rmv_data *)userdata;
+ edev = pci_dev_to_eeh_dev(pdev);
+ if (!edev) {
+ pci_warn(pdev, "EEH: Device removed during processing (#%d)\n",
+ __LINE__);
+ return;
+ }
+
/*
* Actually, we should remove the PCI bridges as well.
* However, that's lots of complexity to do that,
@@ -495,40 +595,50 @@ static void eeh_rmv_device(struct eeh_dev *edev, void *userdata)
* simplicity here.
*/
if (!eeh_edev_actionable(edev) ||
- (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
+ (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
return;
if (rmv_data) {
- driver = eeh_pcid_get(dev);
+ driver = eeh_pcid_get(pdev);
if (driver) {
if (driver->err_handler &&
driver->err_handler->error_detected &&
driver->err_handler->slot_reset) {
- eeh_pcid_put(dev);
+ eeh_pcid_put(pdev);
return;
}
- eeh_pcid_put(dev);
+ eeh_pcid_put(pdev);
}
}
/* Remove it from PCI subsystem */
- pr_info("EEH: Removing %s without EEH sensitive driver\n",
- pci_name(dev));
+ pci_info(pdev, "EEH: Removing device without EEH sensitive driver\n");
edev->mode |= EEH_DEV_DISCONNECTED;
if (rmv_data)
rmv_data->removed_dev_count++;
if (edev->physfn) {
#ifdef CONFIG_PCI_IOV
+ eeh_recovery_unlock();
pci_iov_remove_virtfn(edev->physfn, edev->vf_index);
+ eeh_recovery_lock();
+ /* Both locks are required to make changes */
+ eeh_serialize_lock(&flags);
edev->pdev = NULL;
+ eeh_serialize_unlock(flags);
#endif
if (rmv_data)
list_add(&edev->rmv_entry, &rmv_data->removed_vf_list);
} else {
+ /*
+ * Lock ordering requires that the recovery lock be released
+ * before acquiring the PCI rescan/remove lock.
+ */
+ eeh_recovery_unlock();
pci_lock_rescan_remove();
- pci_stop_and_remove_bus_device(dev);
+ pci_stop_and_remove_bus_device(pdev);
pci_unlock_rescan_remove();
+ eeh_recovery_lock();
}
}
@@ -626,6 +736,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
{
time64_t tstamp;
int cnt, rc;
+ struct pci_dev **pdevs, **pdevp;
struct eeh_dev *edev;
struct eeh_pe *tmp_pe;
bool any_passed = false;
@@ -645,11 +756,23 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
*/
eeh_pe_state_mark(pe, EEH_PE_KEEP);
if (any_passed || driver_eeh_aware || (pe->type & EEH_PE_VF)) {
- eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data);
+ /*
+ * eeh_rmv_device() may need to release the recovery lock to
+ * remove a PCI device so we can't rely on the PE lists staying
+ * valid:
+ */
+ pdevs = pdev_cache_list_create(pe);
+ /* eeh_rmv_device() may re-acquire the recovery lock */
+ for (pdevp = pdevs; pdevp && *pdevp; pdevp++)
+ eeh_rmv_device(*pdevp, rmv_data);
+ pdev_cache_list_destroy(pdevs);
+
} else {
+ eeh_recovery_unlock();
pci_lock_rescan_remove();
pci_hp_remove_devices(bus);
pci_unlock_rescan_remove();
+ eeh_recovery_lock();
}
/*
@@ -665,7 +788,13 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
if (rc)
return rc;
+ /*
+ * The PCI rescan/remove lock must always be taken first, but we need
+ * both here:
+ */
+ eeh_recovery_unlock();
pci_lock_rescan_remove();
+ eeh_recovery_lock();
/* Restore PE */
eeh_ops->configure_bridge(pe);
@@ -673,10 +802,9 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
/* Clear frozen state */
rc = eeh_clear_pe_frozen_state(pe, false);
- if (rc) {
- pci_unlock_rescan_remove();
+ pci_unlock_rescan_remove();
+ if (rc)
return rc;
- }
/* Give the system 5 seconds to finish running the user-space
* hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
@@ -687,7 +815,9 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
if (!driver_eeh_aware || rmv_data->removed_dev_count) {
pr_info("EEH: Sleep 5s ahead of %s hotplug\n",
(driver_eeh_aware ? "partial" : "complete"));
+ eeh_recovery_unlock();
ssleep(5);
+ eeh_recovery_lock();
/*
* The EEH device is still connected with its parent
@@ -701,7 +831,17 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
} else {
if (!driver_eeh_aware)
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
+ /*
+ * Lock ordering requires that the recovery lock be
+ * released before acquiring the PCI rescan/remove
+ * lock.
+ */
+ eeh_recovery_unlock();
+ pci_lock_rescan_remove();
pci_hp_add_devices(bus);
+ pci_unlock_rescan_remove();
+ eeh_recovery_lock();
+
}
}
eeh_pe_state_clear(pe, EEH_PE_KEEP, true);
@@ -709,7 +849,6 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
pe->tstamp = tstamp;
pe->freeze_count = cnt;
- pci_unlock_rescan_remove();
return 0;
}
@@ -837,16 +976,19 @@ void eeh_handle_normal_event(struct eeh_pe *pe)
struct pci_bus *bus;
struct eeh_dev *edev, *tmp;
struct eeh_pe *tmp_pe;
+ struct pci_dev **pdevs, **pdevp;
int rc = 0;
enum pci_ers_result result = PCI_ERS_RESULT_NONE;
struct eeh_rmv_data rmv_data =
{LIST_HEAD_INIT(rmv_data.removed_vf_list), 0};
int devices = 0;
+ eeh_recovery_lock();
bus = eeh_pe_bus_get(pe);
if (!bus) {
pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
__func__, pe->phb->global_number, pe->addr);
+ eeh_recovery_unlock();
return;
}
@@ -948,7 +1090,7 @@ void eeh_handle_normal_event(struct eeh_pe *pe)
/* Get the current PCI slot state. This can take a long time,
* sometimes over 300 seconds for certain systems.
*/
- rc = eeh_wait_state(pe, MAX_WAIT_FOR_RECOVERY * 1000);
+ rc = eeh_wait_state(pe, MAX_WAIT_FOR_RECOVERY * 1000, true);
if (rc < 0 || rc == EEH_STATE_NOT_SUPPORT) {
pr_warn("EEH: Permanent failure\n");
goto recover_failed;
@@ -1079,12 +1221,16 @@ void eeh_handle_normal_event(struct eeh_pe *pe)
* the their PCI config any more.
*/
if (pe->type & EEH_PE_VF) {
- eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
+ pdevs = pdev_cache_list_create(pe);
+ for (pdevp = pdevs; pdevp && *pdevp; pdevp++)
+ eeh_rmv_device(*pdevp, NULL);
+ pdev_cache_list_destroy(pdevs);
eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
} else {
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
+ eeh_recovery_unlock();
pci_lock_rescan_remove();
pci_hp_remove_devices(bus);
pci_unlock_rescan_remove();
@@ -1105,6 +1251,7 @@ void eeh_handle_normal_event(struct eeh_pe *pe)
eeh_clear_slot_attention(edev->pdev);
eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
+ eeh_recovery_unlock();
}
/**
diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index d2873d17d2b1..8f30ad3df8e0 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -103,8 +103,15 @@ int eeh_phb_pe_create(struct pci_controller *phb)
*
* Wait for the state of associated PE. It might take some time
* to retrieve the PE's state.
+ *
+ * Note that if this function sleeps and unlock is true, the EEH recovery lock
+ * will be released and re-acquired.
+ * It is only safe to do this when the PE has the recovering flag set on it.
+ * This is important because the sleep may be
+ * very long (300 seconds) and device removal will be blocked by the recovery
+ * mutex. See eeh_device_notifier().
*/
-int eeh_wait_state(struct eeh_pe *pe, int max_wait)
+int eeh_wait_state(struct eeh_pe *pe, int max_wait, bool unlock)
{
int ret;
int mwait;
@@ -120,6 +127,8 @@ int eeh_wait_state(struct eeh_pe *pe, int max_wait)
#define EEH_STATE_MIN_WAIT_TIME (1000)
#define EEH_STATE_MAX_WAIT_TIME (300 * 1000)
+ WARN_ON_ONCE(unlock && !(pe->state & EEH_PE_RECOVERING));
+
while (1) {
ret = eeh_ops->get_state(pe, &mwait);
@@ -141,8 +150,11 @@ int eeh_wait_state(struct eeh_pe *pe, int max_wait)
__func__, mwait);
mwait = EEH_STATE_MAX_WAIT_TIME;
}
-
+ if (unlock)
+ eeh_recovery_unlock();
msleep(min(mwait, max_wait));
+ if (unlock)
+ eeh_recovery_lock();
max_wait -= mwait;
}
}
@@ -308,6 +320,7 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
{
struct pci_controller *hose = edev->controller;
struct eeh_pe *pe, *parent;
+ unsigned long flags;
/*
* Search the PE has been existing or not according
@@ -315,6 +328,8 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
* PE should be composed of PCI bus and its subordinate
* components.
*/
+ eeh_recovery_must_be_locked();
+ eeh_serialize_lock(&flags);
pe = eeh_pe_get(hose, edev->pe_config_addr);
if (pe) {
if (pe->type & EEH_PE_INVALID) {
@@ -343,8 +358,10 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
list_add_tail(&edev->entry, &pe->edevs);
eeh_edev_dbg(edev, "Added to bus PE\n");
}
+ eeh_serialize_unlock(flags);
return 0;
}
+ eeh_serialize_unlock(flags);
/* Create a new EEH PE */
if (edev->physfn)
@@ -364,6 +381,7 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
* to PHB directly. Otherwise, we have to associate the
* PE with its parent.
*/
+ eeh_serialize_lock(&flags);
if (!new_pe_parent) {
new_pe_parent = eeh_phb_pe_get(hose);
if (!new_pe_parent) {
@@ -371,6 +389,7 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
__func__, hose->global_number);
edev->pe = NULL;
kfree(pe);
+ eeh_serialize_unlock(flags);
return -EEXIST;
}
}
@@ -385,6 +404,7 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
*/
list_add_tail(&edev->entry, &pe->edevs);
edev->pe = pe;
+ eeh_serialize_unlock(flags);
eeh_edev_dbg(edev, "Added to new (parent: PE#%x)\n",
new_pe_parent->addr);
@@ -402,13 +422,18 @@ int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent)
*/
int eeh_pe_tree_remove(struct eeh_dev *edev)
{
+ unsigned long flags;
struct eeh_pe *pe, *parent, *child;
bool keep, recover;
int cnt;
+ /* Both locks are required to make changes */
+ eeh_recovery_must_be_locked();
+ eeh_serialize_lock(&flags);
pe = eeh_dev_to_pe(edev);
if (!pe) {
eeh_edev_dbg(edev, "No PE found for device.\n");
+ eeh_serialize_unlock(flags);
return -EEXIST;
}
@@ -475,6 +500,7 @@ int eeh_pe_tree_remove(struct eeh_dev *edev)
pe = parent;
}
+ eeh_serialize_unlock(flags);
return 0;
}
diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
index a83cb679dd59..12178be1d70a 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
@@ -72,6 +72,7 @@ static ssize_t pnv_eeh_ei_write(struct file *filp,
unsigned long addr, mask;
char buf[50];
int ret;
+ unsigned long flags;
if (!eeh_ops || !eeh_ops->err_inject)
return -ENXIO;
@@ -86,14 +87,21 @@ static ssize_t pnv_eeh_ei_write(struct file *filp,
&pe_no, &type, &func, &addr, &mask);
if (ret != 5)
return -EINVAL;
-
+ /*
+ * Use the spinlock rather than the mutex so that errors can be
+ * injected during slow recovery operations (for testing).
+ */
+ eeh_serialize_lock(&flags);
/* Retrieve PE */
pe = eeh_pe_get(hose, pe_no);
- if (!pe)
+ if (!pe) {
+ eeh_serialize_unlock(flags);
return -ENODEV;
+ }
/* Do error injection */
ret = eeh_ops->err_inject(pe, type, func, addr, mask);
+ eeh_serialize_unlock(flags);
return ret < 0 ? ret : count;
}
diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c
index 1b0c901a6f3b..aeb0ec94dfb8 100644
--- a/arch/powerpc/platforms/pseries/eeh_pseries.c
+++ b/arch/powerpc/platforms/pseries/eeh_pseries.c
@@ -47,11 +47,13 @@ static void pseries_eeh_init_edev(struct pci_dn *pdn);
static void pseries_pcibios_bus_add_device(struct pci_dev *pdev)
{
- struct pci_dn *pdn = pci_get_pdn(pdev);
+ struct pci_dn *pdn;
if (eeh_has_flag(EEH_FORCE_DISABLED))
return;
+ eeh_recovery_lock();
+ pdn = pci_get_pdn(pdev);
dev_dbg(&pdev->dev, "EEH: Setting up device\n");
#ifdef CONFIG_PCI_IOV
if (pdev->is_virtfn) {
@@ -82,6 +84,7 @@ static void pseries_pcibios_bus_add_device(struct pci_dev *pdev)
}
#endif
eeh_probe_device(pdev);
+ eeh_recovery_unlock();
}
diff --git a/arch/powerpc/platforms/pseries/pci_dlpar.c b/arch/powerpc/platforms/pseries/pci_dlpar.c
index 4ba824568119..495dd9204ee5 100644
--- a/arch/powerpc/platforms/pseries/pci_dlpar.c
+++ b/arch/powerpc/platforms/pseries/pci_dlpar.c
@@ -38,8 +38,11 @@ struct pci_controller *init_phb_dynamic(struct device_node *dn)
/* Create EEH devices for the PHB */
eeh_phb_pe_create(phb);
- if (dn->child)
+ if (dn->child) {
+ eeh_recovery_lock();
pseries_eeh_init_edev_recursive(PCI_DN(dn));
+ eeh_recovery_unlock();
+ }
pcibios_scan_phb(phb);
pcibios_finish_adding_to_bus(phb->bus);
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c
index 881d420637bf..7837c9054c73 100644
--- a/drivers/pci/hotplug/pnv_php.c
+++ b/drivers/pci/hotplug/pnv_php.c
@@ -769,7 +769,6 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data)
u16 sts, lsts;
u8 presence;
bool added;
- unsigned long flags;
int ret;
pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts);
@@ -807,10 +806,10 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data)
edev = pchild ? pci_dev_to_eeh_dev(pchild) : NULL;
pe = edev ? edev->pe : NULL;
if (pe) {
- eeh_serialize_lock(&flags);
+ eeh_recovery_lock();
eeh_pe_mark_isolated(pe);
- eeh_serialize_unlock(flags);
eeh_pe_set_option(pe, EEH_OPT_FREEZE_PE);
+ eeh_recovery_unlock();
}
}
diff --git a/drivers/pci/hotplug/rpadlpar_core.c b/drivers/pci/hotplug/rpadlpar_core.c
index 980bb3afd092..1811f24ad151 100644
--- a/drivers/pci/hotplug/rpadlpar_core.c
+++ b/drivers/pci/hotplug/rpadlpar_core.c
@@ -141,7 +141,9 @@ static void dlpar_pci_add_bus(struct device_node *dn)
struct pci_controller *phb = pdn->phb;
struct pci_dev *dev = NULL;
+ eeh_recovery_lock();
pseries_eeh_init_edev_recursive(pdn);
+ eeh_recovery_unlock();
/* Add EADS device to PHB bus, adding new entry to bus->devices */
dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
diff --git a/drivers/vfio/vfio_spapr_eeh.c b/drivers/vfio/vfio_spapr_eeh.c
index 67f55ac1d459..2f184725af5a 100644
--- a/drivers/vfio/vfio_spapr_eeh.c
+++ b/drivers/vfio/vfio_spapr_eeh.c
@@ -54,6 +54,7 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
if (op.argsz < minsz || op.flags)
return -EINVAL;
+ eeh_recovery_lock();
switch (op.op) {
case VFIO_EEH_PE_DISABLE:
ret = eeh_pe_set_option(pe, EEH_OPT_DISABLE);
@@ -84,10 +85,14 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
break;
case VFIO_EEH_PE_INJECT_ERR:
minsz = offsetofend(struct vfio_eeh_pe_op, err.mask);
- if (op.argsz < minsz)
+ if (op.argsz < minsz) {
+ eeh_recovery_unlock();
return -EINVAL;
- if (copy_from_user(&op, (void __user *)arg, minsz))
+ }
+ if (copy_from_user(&op, (void __user *)arg, minsz)) {
+ eeh_recovery_unlock();
return -EFAULT;
+ }
ret = eeh_pe_inject_err(pe, op.err.type, op.err.func,
op.err.addr, op.err.mask);
@@ -95,6 +100,7 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
default:
ret = -EINVAL;
}
+ eeh_recovery_unlock();
}
return ret;
--
2.37.1
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