On Sun, Dec 09, 2018 at 07:08:14PM -0800, Bart Van Assche wrote: > According to what I found in > https://bugzilla.kernel.org/show_bug.cgi?id=201935 patch "block: Clear > kernel memory before copying to user" broke tape access. Hence revert > that patch.
This looks wrong. The patch from Keith is obviously correct for normal usage of bio_copy_user_iov. The SCSI tape drivers use the somewhat odd null_mapped case, so we probably need to refine the checks for that a bit.
