On 18/05/18 15:40, Chris Wilson wrote:
Quoting Lionel Landwerlin (2018-05-18 15:29:21)
On 18/05/18 15:26, Lionel Landwerlin wrote:
On Gen8+ this register is not priviledged and we want to use it in
Mesa to implement a feature required by GPA called Null Hardware. The
idea is to have the command parser turn 3DPRIMITIVE/GPGPU_WALKER into
NOOPs.
This patch just whitelists the bits that we need and that are
currently not used by the kernel.
One thing I don't really know is whether is should be considered an
issue with the current command parser and therefore be backported as a fix.
It would certainly make things easier because we can't really detect the
behavior from userspace.
You can always bump the cmdparser version. The cmdparser doesn't no-op,
it just rejects if a command is outside the whitelist, right? It would
be detectable...
Ah right!
The key question is whether INSTPM is context saved on gen7.
Documentation says it is. I'm not sure I trust it though :(
A test in
gem_exec_parse to confirm we allow INSTPM in the command parser and that
one context does not leak to another would be useful.
Sure.
-Chris
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
