- reduce the irq disabled section, even for a debugfs file this was
way too long.
- protect readers of the captured error state from concurrent freeing
of the same by holding dev->struct_mutex.
- always disable irqs when taking the lock.
Signed-Off-by: Daniel Vetter <daniel.vet...@ffwll.ch>
---
drivers/gpu/drm/i915/i915_debugfs.c | 9 ++++++---
drivers/gpu/drm/i915/i915_dma.c | 2 ++
drivers/gpu/drm/i915/i915_drv.h | 3 +++
drivers/gpu/drm/i915/i915_irq.c | 7 +++++--
4 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
b/drivers/gpu/drm/i915/i915_debugfs.c
index e1c5aa1..63e1c36 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -768,13 +768,16 @@ static int i915_error_state(struct seq_file *m, void
*unused)
unsigned long flags;
int i, page, offset, elt;
+ mutex_lock(&dev->struct_mutex);
spin_lock_irqsave(&dev_priv->error_lock, flags);
- if (!dev_priv->first_error) {
+ error = dev_priv->first_error;
+ spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+
+ if (!error) {
seq_printf(m, "no error state collected\n");
goto out;
}
- error = dev_priv->first_error;
seq_printf(m, "Time: %ld s %ld us\n", error->time.tv_sec,
error->time.tv_usec);
@@ -846,7 +849,7 @@ static int i915_error_state(struct seq_file *m, void
*unused)
intel_display_print_error_state(m, dev, error->display);
out:
- spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+ mutex_unlock(&dev->struct_mutex);
return 0;
}
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index ab3a3fd..0034c6a 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -2153,7 +2153,9 @@ int i915_driver_unload(struct drm_device *dev)
/* Free error state after interrupts are fully disabled. */
del_timer_sync(&dev_priv->hangcheck_timer);
cancel_work_sync(&dev_priv->error_work);
+ mutex_lock(&dev->struct_mutex);
i915_destroy_error_state(dev);
+ mutex_unlock(&dev->struct_mutex);
if (dev->pdev->msi_enabled)
pci_disable_msi(dev->pdev);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 8bb83c0..660b62c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -386,6 +386,9 @@ typedef struct drm_i915_private {
unsigned int fsb_freq, mem_freq, is_ddr3;
spinlock_t error_lock;
+ /* Protected by dev->error_lock. To ensure that the error_state obtained
+ * through this pointer doesn't disappear, you also need to hold
+ * dev->struct_mutex */
struct drm_i915_error_state *first_error;
struct work_struct error_work;
struct completion error_completion;
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index a04d606..c9b0766 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1024,11 +1024,14 @@ void i915_destroy_error_state(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_i915_error_state *error;
+ unsigned long flags;
+
+ WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex));
- spin_lock(&dev_priv->error_lock);
+ spin_lock_irqsave(&dev_priv->error_lock, flags);
error = dev_priv->first_error;
dev_priv->first_error = NULL;
- spin_unlock(&dev_priv->error_lock);
+ spin_unlock_irqrestore(&dev_priv->error_lock, flags);
if (error)
i915_error_state_free(dev, error);
--
1.7.6.4
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
