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 -- 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
