Quoting Bloomfield, Jon (2018-06-14 17:36:29) > > -----Original Message----- > > From: Chris Wilson <[email protected]> > > Sent: Thursday, June 14, 2018 9:07 AM > > To: [email protected] > > Cc: [email protected]; Chris Wilson > > <[email protected]>; > > Bloomfield, Jon <[email protected]>; Joonas Lahtinen > > <[email protected]>; Matthew Auld > > <[email protected]>; David Herrmann > > <[email protected]> > > Subject: [PATCH v2] drm/i915: Prevent writing into a read-only object via a > > GGTT mmap > > > > If the user has created a read-only object, they should not be allowed > > to circumvent the write protection by using a GGTT mmapping. Deny it. > > > > Also most machines do not support read-only GGTT PTEs, so again we have > > to reject attempted writes. Fortunately, this is known a priori, so we > > can at least reject in the call to create the mmap (with a sanity check > > in the fault handler). > > > > v2: Check the vma->vm_flags during mmap() to allow readonly access. > > > > Signed-off-by: Chris Wilson <[email protected]> > > Cc: Jon Bloomfield <[email protected]> > > Cc: Joonas Lahtinen <[email protected]> > > Cc: Matthew Auld <[email protected]> > > Cc: David Herrmann <[email protected]> > > Shame about the BUG_ON, but probably overkill to add code to suppress > the RO flag just for mmap. > > Reviewed-by: Jon Bloomfield <[email protected]>
Maybe one day with a PIN_RO, we can put it back in again. Just a feeling of unease for shadowing cache_level on the vma. If only we could just erase the history of doing cache_domain tracking. -Chris _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
