On Thu, 20 Dec 2012, Linus Torvalds wrote: > On Thu, Dec 20, 2012 at 1:49 PM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: > > On 12/19/2012 08:44 PM, Hugh Dickins wrote: > >> The rmap walks in ksm.c are like those in rmap.c: > >> they can safely be done with anon_vma_lock_read(). > >> > >> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> > >> --- > > > > Hi Hugh, > > > > This patch didn't fix the ksm oopses I'm seeing. > > > > This is with both patches applied: > > Looks like another NULL mm pointer in ksmd.. Hugh fixed one in > 2832bc19f666 ("sched: numa: ksm: fix oops in task_numa_placment()"), > this looks like more of the same. > > At a guess, it looks like get_mergeable_page() has a rmap_item with no > mm. No idea how that happened. Hugh? Some race due to something that > depended on the mmap_sem being exclusive, rather than for > read-ownership? No, it's just a misunderstanding: Sasha's problem is with a linux-next that has Petr's NUMA KSM patch in, and we're still ironing known issues out of that one. Not a problem for 3.8-rc1. Hugh -- 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>