block: Reset buffer alignment on detach

BlockDriverState member buffer_alignment is initially 512.  The device
model may set them, with bdrv_set_buffer_alignment().  If the device
model gets detached (hot unplug), the device's alignment is left
behind.  Only okay because device hot unplug automatically destroys
the BlockDriverState.  But that's a questionable feature, best not to
rely on it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block.c b/block.c
index e9869863d1fb89e077409b27139728f2c0db6db0..b006e586c77a6b4980d872b5e6ec5f4b14fb40ac 100644 (file)
--- a/block.c
+++ b/block.c
@@ -788,6 +788,7 @@ void bdrv_detach_dev(BlockDriverState *bs, void *dev)
     bs->dev = NULL;
     bs->dev_ops = NULL;
     bs->dev_opaque = NULL;
+    bs->buffer_alignment = 512;
 }
 
 /* TODO change to return DeviceState * when all users are qdevified */