On Tue, Feb 26, 2013 at 9:54 AM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: > On 02/25/2013 08:52 PM, KOSAKI Motohiro wrote: >> On Mon, Feb 25, 2013 at 8:30 AM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: >>> Hi all, >>> >>> While fuzzing with trinity inside a KVM tools guest running latest -next kernel, >>> I've stumbled on the following BUG: >>> >>> [13551.830090] ------------[ cut here ]------------ >>> [13551.830090] kernel BUG at mm/mempolicy.c:2187! >>> [13551.830090] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC >> >> Unfortunately, I didn't reproduce this. I'll try it tonight. > > I've actually managed to reproduce it again since then, so it's not a one time > fluke (which is a good sign a I guess). > > It did require about an hour of fuzzing just mm with trinity. > Insert new node after updating node in tree. Hillf --- a/mm/mempolicy.c Tue Feb 26 19:33:20 2013 +++ b/mm/mempolicy.c Tue Feb 26 19:35:38 2013 @@ -2391,8 +2391,8 @@ restart: *mpol_new = *n->policy; atomic_set(&mpol_new->refcnt, 1); sp_node_init(n_new, n->end, end, mpol_new); - sp_insert(sp, n_new); n->end = start; + sp_insert(sp, n_new); n_new = NULL; mpol_new = NULL; break; -- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>