On 03/06, Linus Torvalds wrote: > > On Fri, 5 Mar 2010, akpm@xxxxxxxxxxxxxxxxxxxx wrote: > > > > This patch makes it possible for userspace to implement setproctitle() > > cleanly. It adds a new PR_SET_PROCTITLE_AREA option for prctl(), which > > updates task's mm_struct->arg_start and arg_end to the given area. > > This looks overly complicated. Why do you change the whole locking rules, > instead of protecting _only_ the "arg_start/arg_end" case? > > The thing is, there's no reason to hold the mmap_sem over the whole thing, > and I don't think this is important enough to be a valid reason for > exposing a whole new "locked" access variant, when a simple "protect just > the arg_start/end" would handle it. It was me who suggested to re-use mm->mmap_sem instead of adding the new lock, but looking at this patch again I do not understand the reason this lock should be held throughout in proc_pid_cmdline(). If there is no such a reason, then the new access_process_vm_locked (cough, also suggested by me ;) is not needed. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
