re: octeontx2-af: cn10k: MAC internal loopback support

[Colin Ian King]

Hi,

Static analysis on linux-next today using Coverity found an issue in the
following commit:

commit 3ad3f8f93c81f81d6e28b2e286b03669cc1fb3b0
Author: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
Date:   Thu Feb 11 21:28:34 2021 +0530

    octeontx2-af: cn10k: MAC internal loopback support

The analysis is as follows:

723 static int rvu_cgx_config_intlbk(struct rvu *rvu, u16 pcifunc, bool en)
724 {
725        struct mac_ops *mac_ops;

   1. var_decl: Declaring variable lmac_id without initializer.

726        u8 cgx_id, lmac_id;
727

   2. Condition !is_cgx_config_permitted(rvu, pcifunc), taking false branch.

728        if (!is_cgx_config_permitted(rvu, pcifunc))
729                return -EPERM;
730

    Uninitialized scalar variable (UNINIT)

731        mac_ops = get_mac_ops(rvu_cgx_pdata(cgx_id, rvu));
732

   Uninitialized scalar variable (UNINIT)
   3. uninit_use_in_call: Using uninitialized value lmac_id when calling
*mac_ops->mac_lmac_intl_lbk.

733        return mac_ops->mac_lmac_intl_lbk(rvu_cgx_pdata(cgx_id, rvu),
734                                          lmac_id, en);
735 }

Variables cgx_id and lmac_id are no longer being initialized and garbage
values are being passed into function calls.  Originally, these
variables were being initialized with a call to rvu_get_cgx_lmac_id()
but that has now been removed.

Colin