From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Fri, 02 Aug 2019 09:12:44 +0000 Subject: Re: [PATCH 00/34] put_user_pages(): miscellaneous call sites Message-Id: <20190802091244.GD6461@dhcp22.suse.cz> List-Id: References: <20190802022005.5117-1-jhubbard@nvidia.com> In-Reply-To: <20190802022005.5117-1-jhubbard-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: john.hubbard-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: linux-fbdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Jan Kara , kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Dave Hansen , Dave Chinner , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, sparclinux-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ira Weiny , Dan Williams , devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b@public.gmane.org, rds-devel-N0ozoZBvEnrZJqsBc5GL+g@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Christoph Hellwig , Jason Gunthorpe , xen-devel-GuqFBffKawtpuQazS67q72D2FQJk+8+b@public.gmane.org, devel-urhm25FSIHzptaDgeN77Px2eb7JE58TQ@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, John Hubbard , intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, =?iso-8859-1?B?Suly9G1l?= Glisse , linux-rpi-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, ceph-devel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.orgne On Thu 01-08-19 19:19:31, john.hubbard@gmail.com wrote: [...] > 2) Convert all of the call sites for get_user_pages*(), to > invoke put_user_page*(), instead of put_page(). This involves dozens of > call sites, and will take some time. How do we make sure this is the case and it will remain the case in the future? There must be some automagic to enforce/check that. It is simply not manageable to do it every now and then because then 3) will simply be never safe. Have you considered coccinele or some other scripted way to do the transition? I have no idea how to deal with future changes that would break the balance though. -- Michal Hocko SUSE Labs