powerpc: Always trim numa memory to lmb_end_of_DRAM()
numa_enforce_memory_limit tried to be smart and only call lmb_end_of_DRAM
when a memory limit was set via mem= on the command line. However,
the early boot code will also limit memory added to the lmb system
when iommu=off is specified. When this happens, the page allocator
is given pages not in the linear mapping and this results in a fatal
data reference to the unmapped page.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 195bfcd..eb505ad 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -528,12 +528,10 @@
/*
* We use lmb_end_of_DRAM() in here instead of memory_limit because
* we've already adjusted it for the limit and it takes care of
- * having memory holes below the limit.
+ * having memory holes below the limit. Also, in the case of
+ * iommu_is_off, memory_limit is not set but is implicitly enforced.
*/
- if (! memory_limit)
- return size;
-
if (start + size <= lmb_end_of_DRAM())
return size;