On 2013/3/29 18:48, Glauber Costa wrote: > On 03/29/2013 02:28 PM, Li Zefan wrote: >> The memcg is not referenced, so it can be destroyed at anytime right >> after we exit rcu read section, so it's not safe to access it. >> >> To fix this, we call css_tryget() to get a reference while we're still >> in rcu read section. >> >> This also removes a bogus comment above __memcg_create_cache_enqueue(). >> > Out of curiosity, did you see that happening ? > Just by code inspection. This is not the only place you use RCU in this wrong way. Remember the last patch I sent? ;) > Theoretically, the race you describe seem real, and the fix is sound. > -- 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>