In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: change vm->taskinfo handling This patch changes the handling and lifecycle of vm->taskinfo object. The major changes are: - vm->taskinfo is a dynamically allocated ptr now, and its uasge is reference counted. - introducing two new helper funcs for taskinfo lifecycle management - amdgpuvmgettaskinfo: reference counts up taskinfo before returning this info - amdgpuvmputtaskinfo: reference counts down taskinfo - last put to taskinfo() frees taskinfo from the vm. This patch also does logistical changes required for existing usage of vm->taskinfo. V2: Do not block all the prints when taskinfo not found (Felix) V3: Fixed review comments from Felix - Fix wrong indentation - No debug message for -ENOMEM - Add NULL check for taskinfo - Do not duplicate the debug messages (ti vs no ti) - Get first reference of taskinfo in vminit(), put last in vmfini() V4: Fixed review comments from Felix - fix double reference increment in createtaskinfo - change amdgpuvmgettaskinfopasid - additional changes in amdgpugem.c while porting