On Wed, Apr 05, 2023 at 08:03:57PM -0600, Jens Axboe wrote: > Since SQE memory is shared with userspace, we should only be reading it > once. We cannot read it multiple times, particularly when it's read once > for validation and then read again for the actual use. > > ublk_ch_uring_cmd() is safe when called as a retry operation, as the > memory backing is stable at that point. But for normal issue, we want > to ensure that we only read ublksrv_io_cmd once. Wrap the function in > a helper that reads the value into an on-stack copy of the struct. > > Cc: stable@xxxxxxxxxxxxxxx # 6.0+ > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Thanks, Ming
