[SPARC64]: Fix MD property lifetime bugs.

Property values cannot be referenced outside of
mdesc_grab()/mdesc_release() pairs.  The only major
offender was the VIO bus layer, easily fixed.

Add some commentary to mdesc.h describing these rules.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 2 deletions

diff --git a/include/asm-sparc64/vio.h b/include/asm-sparc64/vio.h
index a8a53e6fc250..83c96422e9d6 100644
--- a/include/asm-sparc64/vio.h
+++ b/include/asm-sparc64/vio.h
@@ -264,12 +264,15 @@ static inline u32 vio_dring_avail(struct vio_dring_state *dr,
                 ((dr->prod - dr->cons) & (ring_size - 1)));
 }
 
+#define VIO_MAX_TYPE_LEN        64
+#define VIO_MAX_COMPAT_LEN      64
+
 struct vio_dev {
         u64                     mp;
         struct device_node      *dp;
 
-        const char              *type;
-        const char              *compat;
+        char                    type[VIO_MAX_TYPE_LEN];
+        char                    compat[VIO_MAX_COMPAT_LEN];
         int                     compat_len;
 
         unsigned long           channel_id;