On Mon, Nov 7, 2016 at 11:28 AM, Christoph Lameter <cl@xxxxxxxxx> wrote: > On Mon, 7 Nov 2016, Thomas Garnier wrote: > >> I am not sure that is possible. kmem_cache_create currently check for >> possible alias, I assume that it goes against what memcg tries to do. > > What does aliasing have to do with this? The aliases must have the same > flags otherwise the caches would not have been merged. > I assume there might be cases where the parent cache and the new memcg cache are compatible for merge (same flags and size). We can bypass that by adding SLAB_NEVER_MERGE but I am not sure what is the consequence of that. >> Separate the changes in two patches might make sense: >> >> 1) Fix the original bug by masking the flags passed to create_cache >> 2) Add flags check in kmem_cache_create. >> >> Does it make sense? > > Sure. > Great, I will send both patches. >> > I also want to make sure that there are no other callers that specify >> > extraneou flags while we are at it. >> I will review as many as I can but we might run into surprises (quick >> boot on defconfig didn't show anything). That's why having two >> different patches might be useful. > > These surprises can be caught later ... Just make sure that the core works > fine with this. You cannot audit all drivers. > Okay, I will. -- Thomas -- 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>