On Tue, 16 Oct 2012, KOSAKI Motohiro wrote: > >> I don't think 80de7c3138ee9fd86a98696fd2cf7ad89b995d0a is right fix. > > > > It's certainly not a complete fix, but I think it's a much better result > > of the race, i.e. we don't panic anymore, we simply fail the read() > > instead. > > Even though 80de7c3138ee9fd86a98696fd2cf7ad89b995d0a itself is simple. It bring > to caller complex. That's not good and have no worth. > Before: the kernel panics, all workloads cease. After: the file shows garbage, all workloads continue. This is better, in my opinion, but at best it's only a judgment call and has no effect on anything. I agree it would be better to respect the return value of mpol_to_str() since there are other possible error conditions other than a freed mempolicy, but let's not consider reverting 80de7c3138. It is obviously not a full solution to the problem, though, and we need to serialize with task_lock(). Dave, are you interested in coming up with a patch? -- 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>