diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
index 599547d..999f201 100644
--- a/arch/arm/lib/bootm.c
+++ b/arch/arm/lib/bootm.c
@@ -69,8 +69,8 @@ void arch_lmb_reserve(struct lmb *lmb)
 	sp = get_sp();
 	debug("## Current stack ends at 0x%08lx ", sp);
 
-	/* adjust sp by 1K to be safe */
-	sp -= 1024;
+	/* adjust sp by 4K to be safe */
+	sp -= 4096;
 	lmb_reserve(lmb, sp,
 		    gd->bd->bi_dram[0].start + gd->bd->bi_dram[0].size - sp);
 }