On 9/7/21 2:29 PM, Yoshihiro Shimoda wrote:
> The cur_tx counter must be incremented after TACT bit of
> txdesc->status was set. However, a CPU is possible to reorder
> instructions and/or memory accesses between cur_tx and
> txdesc->status. And then, if TX interrupt happened at such a
> timing, the sh_eth_tx_free() may free the descriptor wrongly.
> So, add wmb() before cur_tx++.
Not dma_wmb()? :-)
> Otherwise NETDEV WATCHDOG timeout is possible to happen.
>
> Fixes: 86a74ff21a7a ("net: sh_eth: add support for Renesas SuperH Ethernet")
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
[...]
MBR, Sergey
