Quoting Oren Laadan ([email protected]): > The task address space (task->mm) may be shared between processes if > CLONE_VM is used, and particularly among threads. Accordingly, treat > 'task->mm' as a shared object: during checkpoint check against the > objhash and only dump the contents if seen for the first time. During > restart, likewise, only restore if it's a new instance, otherwise use > the one already registered in the objhash. > > Signed-off-by: Oren Laadan <[email protected]>
Cool. Acked-by: Serge Hallyn <[email protected]> Although: > + /* if the mm's objref is in the objhash, use that instance */ > + mm = cr_obj_get_by_ref(ctx, hh->objref, CR_OBJ_MM); > + if (IS_ERR(mm)) { > + ret = PTR_ERR(mm); > + goto out; > + } > > + if (mm) { > + if (mm != current->mm) { In what twisted world could mm == current->mm at restart? > + ret = exec_mmap(mm); > + if (ret < 0) > + goto out; > + atomic_inc(&mm->mm_users); > + } > + ret = 0; > + goto out; > + } > + > + /* otherwise, add our mm to the objhash for future generations */ > mm = current->mm; > + ret = cr_obj_add_ref(ctx, mm, hh->objref, CR_OBJ_MM, 0); > + if (ret < 0) > + goto out; > > /* point of no return -- destruct current mm */ > down_write(&mm->mmap_sem); > diff --git a/include/linux/checkpoint.h b/include/linux/checkpoint.h > index 043535c..1bfe284 100644 > --- a/include/linux/checkpoint.h > +++ b/include/linux/checkpoint.h > @@ -77,6 +77,7 @@ extern void cr_ctx_put(struct cr_ctx *ctx); > enum { > CR_OBJ_FILE = 1, > CR_OBJ_INODE, > + CR_OBJ_MM, > CR_OBJ_MAX > }; > > -- > 1.5.4.3 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
