Messages in this thread |  | | From | Souptick Joarder <> | Date | Sun, 20 Sep 2020 08:33:43 +0530 | Subject | Re: [PATCH] mm/gup: protect unpin_user_pages() against npages==-ERRNO |
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On Thu, Sep 17, 2020 at 1:11 PM Dan Carpenter <dan.carpenter@oracle.com> wrote: > > On Wed, Sep 16, 2020 at 11:57:06PM -0700, John Hubbard wrote: > > As suggested by Dan Carpenter, fortify unpin_user_pages() just a bit, > > against a typical caller mistake: check if the npages arg is really a > > -ERRNO value, which would blow up the unpinning loop: WARN and return. > > > > If this new WARN_ON() fires, then the system *might* be leaking pages > > (by leaving them pinned), but probably not. More likely, gup/pup > > returned a hard -ERRNO error to the caller, who erroneously passed it > > here. > > > > Cc: Ira Weiny <ira.weiny@intel.com> > > Cc: Souptick Joarder <jrdr.linux@gmail.com> > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > > Signed-off-by: John Hubbard <jhubbard@nvidia.com> > > --- > > > > Hi Dan, > > > > Is is OK to use your signed-off-by here? Since you came up with this. > > > > Yeah. That's fine.
Do we need a similar check inside unpin_user_pages_dirty_lock(), when make_dirty set to false ?
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