On Wed, Mar 26, 2014 at 08:04:38AM +0100, Daniel Vetter wrote: > On Wed, Mar 26, 2014 at 07:24:16AM +0100, Daniel Vetter wrote: > > On Tue, Mar 25, 2014 at 07:01:50PM -0700, Ben Widawsky wrote: > > > While the context is not being used, we can make the PTEs invalid, so > > > nothing can accidentally corrupt it. Systems tend to have a lot of > > > trouble when the context gets corrupted. > > > > > > NOTE: This is a slightly different patch than what I posted to Bugzilla. > > > > > > References: https://bugs.freedesktop.org/show_bug.cgi?id=75724 > > > Signed-off-by: Ben Widawsky <ben@xxxxxxxxxxxx> > > > > We could stop the aliasing ppgtt binder from always binding into the > > ppgtt. Which is the bug I'm signed up to fix, and which probably curbs 99% > > of all potential corruption. The last 1% is the kernel getting his > > kmapping wrong ... > > Actually your patch doesn't accomplish much, since MI_UPDATE_GTT only > updates the global gtt, not the aliasing ppgtt. Which means that userspace > batches can still happily stomp all over your precious context objects. > See comment #5 in that bug report: > > https://bugs.freedesktop.org/show_bug.cgi?id=75724#c5 > > Cheers, Daniel Quoting you from comment #5: "ctx objects should only be bound in the global gtt with aliasing ppgtt." The bug was not present with full PPGTT. > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Ben Widawsky, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
