Commits
Oleksandr Andrushchenko committed fa13e665e02
xen/gntdev: Do not destroy context while dma-bufs are in use If there are exported DMA buffers which are still in use and grant device is closed by either normal user-space close or by a signal this leads to the grant device context to be destroyed, thus making it not possible to correctly destroy those exported buffers when they are returned back to gntdev and makes the module crash: [ 339.617540] [<ffff00000854c0d8>] dmabuf_exp_ops_release+0x40/0xa8 [ 339.617560] [<ffff00000867a6e8>] dma_buf_release+0x60/0x190 [ 339.617577] [<ffff0000082211f0>] __fput+0x88/0x1d0 [ 339.617589] [<ffff000008221394>] ____fput+0xc/0x18 [ 339.617607] [<ffff0000080ed4e4>] task_work_run+0x9c/0xc0 [ 339.617622] [<ffff000008089714>] do_notify_resume+0xfc/0x108 Fix this by referencing gntdev on each DMA buffer export and unreferencing on buffer release. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Reviewed-by: Boris Ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>