From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sukadev Bhattiprolu Subject: Re: [RFC][v8][PATCH 10/10]: Document clone3() syscall Date: Wed, 14 Oct 2009 11:39:16 -0700 Message-ID: <20091014183916.GA3515@us.ibm.com> References: <20091013044925.GA28181@us.ibm.com> <20091013045556.GJ28435@us.ibm.com> <200910141426.35338.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <200910141426.35338.arnd-r2nGTMty4D4@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Arnd Bergmann Cc: randy.dunlap-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, Containers , Nathan Lynch , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Louis.Rilling-aw0BnHfMbSpBDgjK7y7TUQ@public.gmane.org, "Eric W. Biederman" , kosaki.motohiro-+CUm20s59erQFUHtdCDX3A@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, Alexey Dobriyan , roland-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Pavel Emelyanov List-Id: linux-api@vger.kernel.org Arnd Bergmann [arndbergmann-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org] wrote: | On Tuesday 13 October 2009, Sukadev Bhattiprolu wrote: | > +clone3(struct clone_struct * __user clone_args, pid_t * __user pids) | > + | > + In addition to doing everything that clone() system call does, | > + the clone3() system call: | > + | > + - allows additional clone flags (all 32 bits in the flags | > + parameter to clone() are in use) | > + | > + - allows user to specify a pid for the child process in its | > + active and ancestor pid name spaces. | | Someone (sorry, can't find the old mail) pointed out last time that | the 'pid_t *__user tidptr' argument needs to be an independent pointer, | in order to allow the same use patterns with CLONE_CHILD_SETTID and | CLONE_CHILD_CLEARTID that you can do with the current clone | implementation. I think it was Oren Laadan. | | Moving that argument from clone_struct into the argument list would | also make this a three-argument syscall, which solves the naming problem. How about we pull 'nr_pids' out of clone_args struct and make that a separate parameter. It seems the odd man out and controls the pid_t list parameter. | | Arnd <><