1 files changed, 6 insertions, 1 deletions

diff --git a/include/asm-powerpc/mmu_context.h b/include/asm-powerpc/mmu_context.h
index 8c6b1a6d944f..083ac917bd29 100644
--- a/include/asm-powerpc/mmu_context.h
+++ b/include/asm-powerpc/mmu_context.h
@@ -25,8 +25,13 @@ static inline void enter_lazy_tlb(struct mm_struct *mm,
 {
 }
 
+/*
+ * The proto-VSID space has 2^35 - 1 segments available for user mappings.
+ * Each segment contains 2^28 bytes.  Each context maps 2^44 bytes,
+ * so we can support 2^19-1 contexts (19 == 35 + 28 - 44).
+ */
 #define NO_CONTEXT      0
-#define MAX_CONTEXT     (0x100000-1)
+#define MAX_CONTEXT     ((1UL << 19) - 1)
 
 extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
 extern void destroy_context(struct mm_struct *mm);