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    SubjectRe: [PATCH] fix NULL-pointer dereference on scsi_run_queue
    > I'm afraid that without the second half of that patch the following race
    > is still possible:
    > - sdev reference count drops to zero while scsi_run_queue() is in
    > progress and while that sdev is on the starved_list of its SCSI host;
    > scsi_device_dev_release_usercontext() call is scheduled but not yet
    > executed.
    > - scsi_run_queue() takes that sdev off the local starved_list.
    > - scsi_run_queue() calls get_device() and that call fails since the
    > sdev reference count is zero.
    > - scsi_device_dev_release_usercontext() gets scheduled and frees the
    > sdev.
    > - scsi_run_queue() proceeds and calls __blk_run_queue() on a freed
    > queue, which is what we were trying to avoid.
    Thank you for the explanation. It look correct. Let's check one more thing.
    What If __scsi_remove_device doesn't release device? : reference count
    is more than 2.
    So We lost starved_list but device is exist. Is there any issue about this?


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