Re: [BUG][5.20] refcount_t: underflow; use-after-free

[Maíra Canal]

Hi Mikhail

Looks like this use-after-free problem was introduced on
90af0ca047f3049c4b46e902f432ad6ef1e2ded6. Checking this patch it seems
like: if amdgpu_cs_vm_handling return r != 0, then it will unlock
bo_list_mutex inside the function amdgpu_cs_vm_handling and again on
amdgpu_cs_parser_fini.

Maybe the following patch will help:

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