Erroneous logic was duplicated from add_ext_regions() into
add_hwdom_free_regions(). Frame numbers are converted to addresses, but
the end address (e) is rounded down to page size alignment. The logic to
calculate the size assumes e points to the last address, not page,
effectively leading to the region size being erroneously calculated to
be 2M smaller than the actual size of the region.

Fix by adding 1 to the frame number before converting back to address.

Fixes: 02975cc38389 ("xen/arm: permit non direct-mapped Dom0 construction")
Signed-off-by: Stewart Hildebrand <stewart.hildebr...@amd.com>
---
 xen/arch/arm/domain_build.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 2f655bcc2237..a0f3c074337d 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -905,7 +905,7 @@ static int __init add_hwdom_free_regions(unsigned long 
s_gfn,
     struct membanks *free_regions = data;
     paddr_t start, size;
     paddr_t s = pfn_to_paddr(s_gfn);
-    paddr_t e = pfn_to_paddr(e_gfn);
+    paddr_t e = pfn_to_paddr(e_gfn + 1) - 1;
     unsigned int i, j;
 
     if ( free_regions->nr_banks >= free_regions->max_banks )
-- 
2.49.0


Reply via email to