> -----Original Message-----
> From: Hans de Goede <hdegoede@xxxxxxxxxx>
> Sent: Wednesday, 4 October 2023 12:38
> To: Dan Carpenter <dan.carpenter@xxxxxxxxxx>; Liming Sun
> <limings@xxxxxxxxxx>; Vadim Pasternak <vadimp@xxxxxxxxxx>; David
> Thompson <davthompson@xxxxxxxxxx>
> Cc: platform-driver-x86@xxxxxxxxxxxxxxx
> Subject: Re: [bug report] platform/mellanox: Add BlueField-3 support in the
> tmfifo driver
>
> +Cc Vadim, David.
>
> On 9/28/23 14:23, Dan Carpenter wrote:
> > Hello Liming Sun,
> >
> > The patch bc05ea63b394: "platform/mellanox: Add BlueField-3 support in
> > the tmfifo driver" from Oct 18, 2022 (linux-next), leads to the
> > following Smatch static checker warning:
> >
> > drivers/platform/mellanox/mlxbf-tmfifo.c:634
> mlxbf_tmfifo_rxtx_word()
> > error: uninitialized symbol 'data'.
>
> Dan as always thank you for reporting this.
>
> Liming, David, Vadim,
>
> Can one of you take a look at this please ?
>
> Regards,
>
> Hans
>
Hi Hans,
Sure. We'll handle it.
Thanks,
Vadim.
>
>
> >
> > drivers/platform/mellanox/mlxbf-tmfifo.c
> > 592 static void mlxbf_tmfifo_rxtx_word(struct mlxbf_tmfifo_vring *vring,
> > 593 struct vring_desc *desc,
> > 594 bool is_rx, int len)
> > 595 {
> > 596 struct virtio_device *vdev = vring->vq->vdev;
> > 597 struct mlxbf_tmfifo *fifo = vring->fifo;
> > 598 void *addr;
> > 599 u64 data;
> > 600
> > 601 /* Get the buffer address of this desc. */
> > 602 addr = phys_to_virt(virtio64_to_cpu(vdev, desc->addr));
> > 603
> > 604 /* Read a word from FIFO for Rx. */
> > 605 if (is_rx)
> > 606 data = readq(fifo->rx.data);
> > 607
> > 608 if (vring->cur_len + sizeof(u64) <= len) {
> > 609 /* The whole word. */
> > 610 if (!IS_VRING_DROP(vring)) {
> > 611 if (is_rx)
> > 612 memcpy(addr + vring->cur_len, &data,
> > 613 sizeof(u64));
> > 614 else
> > 615 memcpy(&data, addr + vring->cur_len,
> > 616 sizeof(u64));
> > 617 }
> >
> > if IS_VRING_DROP() is true then data isn't intialized.
> >
> > 618 vring->cur_len += sizeof(u64);
> > 619 } else {
> > 620 /* Leftover bytes. */
> > 621 if (!IS_VRING_DROP(vring)) {
> > 622 if (is_rx)
> > 623 memcpy(addr + vring->cur_len, &data,
> > 624 len - vring->cur_len);
> > 625 else
> > 626 memcpy(&data, addr + vring->cur_len,
> > 627 len - vring->cur_len);
> > 628 }
> >
> > Same here.
> >
> > 629 vring->cur_len = len;
> > 630 }
> > 631
> > 632 /* Write the word into FIFO for Tx. */
> > 633 if (!is_rx)
> > --> 634 writeq(data, fifo->tx.data);
> > ^^^^
> > Unitialized if IS_VRING_DROP() is true.
> >
> > 635 }
> >
> > regards,
> > dan carpenter
> >
