From: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
Trying to remove an "empty" (just initialized, or "cleared") interval
from the tree, this results in an endless loop.
As we typically protect the tree with a spinlock_irq,
the result is a hung system.
Be nice to error cleanup code paths, ignore removal of empty intervals.
Signed-off-by: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@xxxxxxxxxx>
---
drivers/block/drbd/drbd_interval.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/block/drbd/drbd_interval.c b/drivers/block/drbd/drbd_interval.c
index 5024ffd6143d..b6aaf0d4d85b 100644
--- a/drivers/block/drbd/drbd_interval.c
+++ b/drivers/block/drbd/drbd_interval.c
@@ -95,6 +95,10 @@ drbd_contains_interval(struct rb_root *root, sector_t sector,
void
drbd_remove_interval(struct rb_root *root, struct drbd_interval *this)
{
+ /* avoid endless loop */
+ if (drbd_interval_empty(this))
+ return;
+
rb_erase_augmented(&this->rb, root, &augment_callbacks);
}
--
2.38.1
