From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Serge E. Hallyn" Subject: Re: [PATCH 3/3] c/r: define s390-specific checkpoint-restart code (v6) Date: Wed, 25 Feb 2009 17:34:54 -0600 Message-ID: <20090225233454.GA29972@us.ibm.com> References: <1235585529-806-1-git-send-email-danms@us.ibm.com> <1235585529-806-4-git-send-email-danms@us.ibm.com> <20090225162817.2003383c@thinkcentre.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20090225162817.2003383c-4v5LP+xe+1byhTdZtsIeww@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: Nathan Lynch Cc: containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, Dan Smith List-Id: containers.vger.kernel.org Quoting Nathan Lynch (ntl-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org): > > +#if 0 > > + /* Oren's v13 is on an older kernel which has no vdso_base > > + * on newer kernel, we'll have to enable this > > + */ > > + CR_COPY(op, hh->vdso_base, mm->context.vdso_base); > > +#endif > > During restart, does this replace the current task's VDSO contents, and > if so, is that wise? VDSO areas contain things like timestamps for > gettimeofday()... (I've gone back and forth on this, and the following answer differs from any interpretation i've had before :) Well, arch_setup_additional_pages() uses get_unmapped_area() to get a user mapping for the vdso pages. So i would expect that in fact the arch-independent code would set up a new vdso mapping at the checkpointed location, and so mm->context.vdso_base does in fact need to be changed. But it's something to verify when we port the code to a newer kernel. -serge