CVE-2024-41008

In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu: change vm->task_info handling

This patch changes the handling and lifecycle of vm->task_info object.

The major changes are:

- vm->task_info is a dynamically allocated ptr now, and its uasge is

reference counted.

- introducing two new helper funcs for task_info lifecycle management

- amdgpu_vm_get_task_info: reference counts up task_info before

returning this info

- amdgpu_vm_put_task_info: reference counts down task_info

- last put to task_info() frees task_info from the vm.

This patch also does logistical changes required for existing usage

of vm->task_info.

V2: Do not block all the prints when task_info not found (Felix)

V3: Fixed review comments from Felix

- Fix wrong indentation

- No debug message for -ENOMEM

- Add NULL check for task_info

- Do not duplicate the debug messages (ti vs no ti)

- Get first reference of task_info in vm_init(), put last

in vm_fini()

V4: Fixed review comments from Felix

- fix double reference increment in create_task_info

- change amdgpu_vm_get_task_info_pasid

- additional changes in amdgpu_gem.c while porting