Quoting Bloomfield, Jon (2018-06-14 17:36:29) > > -----Original Message----- > > From: Chris Wilson <ch...@chris-wilson.co.uk> > > Sent: Thursday, June 14, 2018 9:07 AM > > To: intel-...@lists.freedesktop.org > > Cc: dri-devel@lists.freedesktop.org; Chris Wilson > > <ch...@chris-wilson.co.uk>; > > Bloomfield, Jon <jon.bloomfi...@intel.com>; Joonas Lahtinen > > <joonas.lahti...@linux.intel.com>; Matthew Auld > > <matthew.william.a...@gmail.com>; David Herrmann > > <dh.herrm...@gmail.com> > > 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 <ch...@chris-wilson.co.uk> > > Cc: Jon Bloomfield <jon.bloomfi...@intel.com> > > Cc: Joonas Lahtinen <joonas.lahti...@linux.intel.com> > > Cc: Matthew Auld <matthew.william.a...@gmail.com> > > Cc: David Herrmann <dh.herrm...@gmail.com> > > Shame about the BUG_ON, but probably overkill to add code to suppress > the RO flag just for mmap. > > Reviewed-by: Jon Bloomfield <jon.bloomfi...@intel.com>
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 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
