[PATCH 1/5] iommu/x86: fix IVMD/RMRR range checker loop increment

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

mfn_add() doesn't store the incremented value in the parameter, and instead
returns it to the caller.  As a result, the loop in iommu_unity_region_ok()
didn't make progress.  Fix it by storing the incremented value.

Fixes: e45801dea17b ('iommu/x86: introduce a generic IVMD/RMRR range validity 
helper')
Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
 xen/drivers/passthrough/x86/iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/drivers/passthrough/x86/iommu.c 
b/xen/drivers/passthrough/x86/iommu.c
index 1c8cf3271a09..a3fa0aef7c37 100644
--- a/xen/drivers/passthrough/x86/iommu.c
+++ b/xen/drivers/passthrough/x86/iommu.c
@@ -804,7 +804,7 @@ bool __init iommu_unity_region_ok(const char *prefix, mfn_t 
start, mfn_t end)
            "%s: [%#" PRI_mfn " ,%#" PRI_mfn "] is not (entirely) in reserved 
memory\n",
            prefix, mfn_x(start), mfn_x(end));
 
-    for ( addr = start; mfn_x(addr) <= mfn_x(end); mfn_add(addr, 1) )
+    for ( addr = start; mfn_x(addr) <= mfn_x(end); addr = mfn_add(addr, 1) )
     {
         unsigned int type = page_get_ram_type(addr);
 
-- 
2.43.0