From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [v12][PATCH 0/9] Implement eclone() syscall Date: Thu, 19 Nov 2009 15:20:46 +0100 Message-ID: <200911191520.46445.arnd@arndb.de> References: <20091111043440.GA9377@suka> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20091111043440.GA9377@suka> 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: Sukadev Bhattiprolu Cc: mtk.manpages-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org, Containers , Nathan Lynch , matthltc-npbjlsIvGkV82hYKe6nXyg@public.gmane.org, "Eric W. Biederman" , hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Alexey Dobriyan , roland-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Pavel Emelyanov List-Id: containers.vger.kernel.org On Wednesday 11 November 2009, Sukadev Bhattiprolu wrote: > Based on these requirements and constraints, we explored a couple of system > call interfaces (in earlier versions of this patchset). Based on input from > Arnd Bergmann and others, the new interface of the system call is: > > struct clone_args { > u64 clone_flags_high; > u64 child_stack_base; > u64 child_stack_size; > u64 parent_tid_ptr; > u64 child_tid_ptr; > u32 nr_pids; > u32 reserved0; > u64 reserved1; > }; > > sys_eclone(u32 flags_low, struct clone_args *cargs, int args_size, > pid_t *pids) Sorry if I'm beating a dead horse here, but having three methods for possible extensions (flags, args_size and reserved fields) is going a bit too far, as I think we've discussed a few times before. The flags field seems necessary and the reserved fields are moderately sensible if you don't have the args_size argument (a flag could still express the same), but if you have args_size I see no point in reserving space. I'd much prefer if you could get rid of the args_size, but if other insist on keeping that, please loose the redundant reserved fields at the end. Alternatively, just keep my name out of it ;-) Arnd <><