https://syzkaller.appspot.com/bug?id=163388d1fb80146cd3ba22a11a5a1995c3eaaafe
WARNING in dma_buf_vunmap
warningdmabuf
https://lkml.iu.edu/hypermail/linux/kernel/1907.2/01548.html
Linux-Kernel Archive: Re: [PATCH 3/3] mm/vmalloc: Sync unmappings in vunmap_page_range()