The DT spec declares only two number types for a property: u32 and u64,
as per Table 2.3 in Section 2.2.4. Remove unbounded loop and replace
with a switch statement. Default to a size of 1 cell in the nonsensical
size case, with a warning printed on the Xen console.
Suggested-by: Daniel P. Smith" <dpsm...@apertussolutions.com>
Signed-off-by: Alejandro Vallejo <agarc...@amd.com>
---
v2:
* Added missing `break` on the `case 2:` branch and added
ASSERT_UNREACHABLE() to the deafult path
---
xen/include/xen/device_tree.h | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
index 75017e4266..2ec668b94a 100644
--- a/xen/include/xen/device_tree.h
+++ b/xen/include/xen/device_tree.h
@@ -261,10 +261,21 @@ void intc_dt_preinit(void);
/* Helper to read a big number; size is in cells (not bytes) */
static inline u64 dt_read_number(const __be32 *cell, int size)
{
- u64 r = 0;
+ u64 r = be32_to_cpu(*cell);
+
+ switch ( size )
+ {
+ case 1:
+ break;
+ case 2:
+ r = (r << 32) | be32_to_cpu(cell[1]);
+ break;
+ default:
+ // Nonsensical size. default to 1.
+ printk(XENLOG_WARNING "dt_read_number(%d) bad size\n", size);
+ ASSERT_UNREACHABLE();
+ };
- while ( size-- )
- r = (r << 32) | be32_to_cpu(*(cell++));
return r;
}
base-commit: 14c57887f36937c1deb9eeca852c3a7595d2d0b8
--
2.43.0
