diff --git a/sys/powerpc/powerpc/busdma_machdep.c b/sys/powerpc/powerpc/busdma_machdep.c
index 802b2105b546..ba27713a7008 100644
--- a/sys/powerpc/powerpc/busdma_machdep.c
+++ b/sys/powerpc/powerpc/busdma_machdep.c
@@ -418,6 +418,8 @@ bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dma_segment_t segs[],
 		 * Compute the segment size, and adjust counts.
 		 */
 		sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
+		if (sgsize > dmat->maxsegsz)
+			sgsize = dmat->maxsegsz;
 		if (buflen < sgsize)
 			sgsize = buflen;