Comment 23 for bug 1561830

I have now finished bisecting the mainline kernel, and this is the commit that causes this problem:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=64d513ac31bd02a3c9b69ef04444f36c196f9a9d

commit 64d513ac31bd02a3c9b69ef04444f36c196f9a9d
Author: Christoph Hellwig <email address hidden>
Date: Thu Oct 8 09:28:04 2015 +0100

    scsi: use host wide tags by default

    This patch changes the !blk-mq path to the same defaults as the blk-mq
    I/O path by always enabling block tagging, and always using host wide
    tags. We've had blk-mq available for a few releases so bugs with
    this mode should have been ironed out, and this ensures we get better
    coverage of over tagging setup over different configs.

    Signed-off-by: Christoph Hellwig <email address hidden>
    Acked-by: Jens Axboe <email address hidden>
    Reviewed-by: Hannes Reinecke <email address hidden>
    Signed-off-by: James Bottomley <email address hidden>