On Mon, Apr 02, 2012 at 08:19:59PM +0400, Konstantin Khlebnikov wrote: > Oleg Nesterov wrote: > >On 04/02, Konstantin Khlebnikov wrote: > >> > >>In this patch I leave mm->exe_file lockless. > >>After exec/fork we can change it only for current task and only if mm->mm_users == 1. > >> > >>something like this: > >> > >>task_lock(current); > > > >OK, this protects against the race with get_task_mm() > > > >>if (atomic_read(¤t->mm->mm_users) == 1) > > > >this means PR_SET_MM_EXE_FILE can fail simply because someone did > >get_task_mm(). Or the caller is multithreaded. > > This is sad, seems like we should keep mm->exe_file protection by mm->mmap_sem. > So, I'll rework this patch... Ah, it's about locking. I misundertand it at first. Oleg, forget about my email then. Cyrill -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>