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There is a rare race condition when preparing for a reset where guc_lrc_desc_unpin() could be in the process of deregistering a context while a different thread is scrubbing outstanding contexts and it alters the context state and does a wakeref put. Then, if there is a failure with deregister_context(), a second wakeref put could occur. As a result the wakeref count could drop below 0 and fail an INTEL_WAKEREF_BUG_ON() check. Therefore if there is a failure with deregister_context(), undo the context state changes and do a wakeref put only if the context was set to be destroyed earlier. v2: Expand comment to better explain change. (Daniele) v3: Removed addition to the original comment. (Daniele) Fixes:2f2cc53b5f("drm/i915/guc: Close deregister-context race against CT-loss") Signed-off-by: Jesus Narvaez <jesus.narvaez@intel.com> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Alan Previn <alan.previn.teres.alexis@intel.com> Cc: Anshuman Gupta <anshuman.gupta@intel.com> Cc: Mousumi Jana <mousumi.jana@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Signed-off-by: John Harrison <John.C.Harrison@Intel.com> Link: https://lore.kernel.org/r/20250528230551.1855177-1-jesus.narvaez@intel.com (cherry picked from commitf36a75aba1) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>