[PATCH] nvmet-tcp: fix data digest pointer calculation

[Varun Prakash]

On Thu, Oct 28, 2021 at 11:26:02AM +0300, Sagi Grimberg wrote:
> 
> >>>>>>diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
> >>>>>>index 07ee347..d641bfa 100644
> >>>>>>--- a/drivers/nvme/target/tcp.c
> >>>>>>+++ b/drivers/nvme/target/tcp.c
> >>>>>>@@ -702,7 +702,7 @@ static int nvmet_try_send_ddgst(struct nvmet_tcp_cmd *cmd, bool last_in_batch)
> >>>>>>   	struct nvmet_tcp_queue *queue = cmd->queue;
> >>>>>>   	struct msghdr msg = { .msg_flags = MSG_DONTWAIT };
> >>>>>>   	struct kvec iov = {
> >>>>>>-		.iov_base = &cmd->exp_ddgst + cmd->offset,
> >>>>>>+		.iov_base = (u8 *)&cmd->exp_ddgst + cmd->offset,
> >>>>>
> >>>>>Wouldn't be the better fix to divide cmd->offset by 4 instead of the
> >>>>>casts?  I can fix this up inline if that is ok.
> >>>>
> >>>>Don't really mind, what makes it a better fix?
> >>>
> >>>I generally prefer to avoid casts as they paper over bugs.
> >>
> >>I'm fine either way.
> >
> >cmd->offset can have value 0,1,2,3. cmd->offset / 4 will always be 0.
> >If 2 bytes of digest are transmitted in the first call to kernel_sendmsg()
> >then in the second call remaining 2 bytes has to be transmitted so data digest
> >buffer pointer should increase by 2 bytes.
> 
> Right, so let's just change the cast to (void *). Varun, can you respin
> the patches?

Both the patches are already applied to nvme-5.15, should I send v2 or
create a new patch for u8 * -> void * change?