Explain why wbinv_all is SMP-safe in this case, and add a missing l2 cache

flush.  (Either it was missing here, or it isn't needed in the minidump
case.  Adding it here seems like the safer path to consistancy.)

1 files changed, 7 insertions, 1 deletions

diff --git a/sys/arm/arm/dump_machdep.c b/sys/arm/arm/dump_machdep.c
index e8ba5768..f37346c 100644
--- a/sys/arm/arm/dump_machdep.c
+++ b/sys/arm/arm/dump_machdep.c
@@ -174,8 +174,14 @@ cb_dumpdata(struct md_pa *mdp, int seqnr, void *arg)
 	printf("  chunk %d: %dMB (%d pages)", seqnr, pgs * PAGE_SIZE / (
 	    1024*1024), pgs);
 
-	/* Make sure we write coherent datas. */
+	/*
+	 * Make sure we write coherent data.  Note that in the SMP case this
+	 * only operates on the L1 cache of the current CPU, but all other CPUs
+	 * have already been stopped, and their flush/invalidate was done as
+	 * part of stopping.
+	 */
 	cpu_idcache_wbinv_all();
+	cpu_l2cache_wbinv_all();
 #ifdef __XSCALE__
 	xscale_cache_clean_minidata();
 #endif