Re: [PATCH v4 3.0-rc2-tip 4/22] 4: Uprobes: register/unregister probes.

Srikar Dronamraju
2011-06-14T12:08:23Z

* Oleg Nesterov <oleg@redhat.com> [2011-06-13 21:57:01]:

> On 06/07, Srikar Dronamraju wrote:
> >
> > +int register_uprobe(struct inode *inode, loff_t offset,
> > + struct uprobe_consumer *consumer)
> > +{
> > + struct prio_tree_iter iter;
> > + struct list_head try_list, success_list;
> > + struct address_space *mapping;
> > + struct mm_struct *mm, *tmpmm;
> > + struct vm_area_struct *vma;
> > + struct uprobe *uprobe;
> > + int ret = -1;
> > +
> > + if (!inode || !consumer || consumer->next)
> > + return -EINVAL;
> > +
> > + if (offset > inode->i_size)
> > + return -EINVAL;
> > +
> > + uprobe = alloc_uprobe(inode, offset);
> > + if (!uprobe)
> > + return -ENOMEM;
> > +
> > + INIT_LIST_HEAD(&try_list);
> > + INIT_LIST_HEAD(&success_list);
> > + mapping = inode->i_mapping;
> > +
> > + mutex_lock(&uprobes_mutex);
> > + if (uprobe->consumers) {
> > + ret = 0;
> > + goto consumers_add;
> > + }
> > +
> > + mutex_lock(&mapping->i_mmap_mutex);
> > + vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, 0) {
>
> I didn't actually read this patch yet, but this looks suspicious.
> Why begin == end == 0? Doesn't this mean we are ignoring the mappings
> with vm_pgoff != 0 ?
>
> Perhaps this should be offset >> PAGE_SIZE?
>

Okay,
I guess you meant something like this.

vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {

where pgoff == offset >> PAGE_SIZE
Right?

--
Thanks and Regards
Srikar