drm/i915/gt: Check we are the Ironlake IPS provider before deregistering

Check that we own the global pointer before deregistering.

Reported-by: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191210153620.3929372-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2019-12-10 15:36:20 +00:00
parent 00aff3f6d8
commit c0168a3ee6

View File

@ -1715,6 +1715,7 @@ void intel_rps_driver_register(struct intel_rps *rps)
* set up, to avoid intel-ips sneaking in and reading bogus values.
*/
if (IS_GEN(gt->i915, 5)) {
GEM_BUG_ON(ips_mchdev);
rcu_assign_pointer(ips_mchdev, gt->i915);
ips_ping_for_i915_load();
}
@ -1722,6 +1723,7 @@ void intel_rps_driver_register(struct intel_rps *rps)
void intel_rps_driver_unregister(struct intel_rps *rps)
{
if (ips_mchdev == rps_to_i915(rps))
rcu_assign_pointer(ips_mchdev, NULL);
}