On Mon 20 May 06:53 PDT 2019, Alex Elder wrote:
> The C bit-fields in the first byte of the rmnet_map_header structure
> are defined in the wrong order. The first byte should be formatted
> this way:
> +------- reserved_bit
> | +----- cd_bit
> | |
> v v
> +-----------+-+-+
> | pad_len |R|C|
> +-----------+-+-+
> 7 6 5 4 3 2 1 0 <-- bit position
>
> But the C bit-fields that define the first byte are defined this way:
> u8 pad_len:6;
> u8 reserved_bit:1;
> u8 cd_bit:1;
>
> And although this isn't portable, I can state that when I build it
> the result puts the bit-fields in the wrong location (e.g., the
> cd_bit is in bit position 7, when it should be position 0).
>
> Fix this by reordering the definitions of these struct members.
> Upcoming patches will reimplement these definitions portably.
>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Regards,
Bjorn
> Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> ---
> drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> index 884f1f52dcc2..b1ae9499c0b2 100644
> --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> @@ -40,9 +40,9 @@ enum rmnet_map_commands {
> };
>
> struct rmnet_map_header {
> - u8 pad_len:6;
> - u8 reserved_bit:1;
> u8 cd_bit:1;
> + u8 reserved_bit:1;
> + u8 pad_len:6;
> u8 mux_id;
> __be16 pkt_len;
> } __aligned(1);
> --
> 2.20.1
>
