RE: Coverity: dm_dmub_sw_init(): Incorrect expression

From: Limonciello, Mario
Date: Thu Jan 12 2023 - 17:39:32 EST


[AMD Official Use Only - General]

This particular one was fixed already in https://patchwork.freedesktop.org/patch/518050/ which got applied today.

> -----Original Message-----
> From: coverity-bot <keescook@xxxxxxxxxxxx>
> Sent: Thursday, January 12, 2023 16:25
> To: Limonciello, Mario <Mario.Limonciello@xxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; Siqueira,
> Rodrigo <Rodrigo.Siqueira@xxxxxxx>; Li, Sun peng (Leo)
> <Sunpeng.Li@xxxxxxx>; Li, Roman <Roman.Li@xxxxxxx>; Zuo, Jerry
> <Jerry.Zuo@xxxxxxx>; Wu, Hersen <hersenxs.wu@xxxxxxx>; dri-
> devel@xxxxxxxxxxxxxxxxxxxxx; Koenig, Christian <Christian.Koenig@xxxxxxx>;
> Lazar, Lijo <Lijo.Lazar@xxxxxxx>; Pillai, Aurabindo
> <Aurabindo.Pillai@xxxxxxx>; Wentland, Harry <Harry.Wentland@xxxxxxx>;
> Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Daniel Vetter
> <daniel@xxxxxxxx>; David Airlie <airlied@xxxxxxxxx>; Pan, Xinhui
> <Xinhui.Pan@xxxxxxx>; Wheeler, Daniel <Daniel.Wheeler@xxxxxxx>;
> Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>; linux-next@xxxxxxxxxxxxxxx;
> linux-hardening@xxxxxxxxxxxxxxx
> Subject: Coverity: dm_dmub_sw_init(): Incorrect expression
>
> Hello!
>
> This is an experimental semi-automated report about issues detected by
> Coverity from a scan of next-20230111 as part of the linux-next scan project:
> https://scan.coverity.com/projects/linux-next-weekly-scan
>
> You're getting this email because you were associated with the identified
> lines of code (noted below) that were touched by commits:
>
> Tue Jan 10 14:32:57 2023 -0500
> a7ab345149b8 ("drm/amd/display: Load DMUB microcode during early_init")
>
> Coverity reported the following:
>
> *** CID 1530544: Incorrect expression (IDENTICAL_BRANCHES)
> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c:1951 in
> dm_dmub_sw_init()
> 1945
> 1946 switch (adev->ip_versions[DCE_HWIP][0]) {
> 1947 case IP_VERSION(2, 1, 0):
> 1948 dmub_asic = DMUB_ASIC_DCN21;
> 1949 break;
> 1950 case IP_VERSION(3, 0, 0):
> vvv CID 1530544: Incorrect expression (IDENTICAL_BRANCHES)
> vvv The same code is executed regardless of whether "adev-
> >ip_versions[GC_HWIP][0] == 656128U" is true, because the 'then' and 'else'
> branches are identical. Should one of the branches be modified, or the entire 'if'
> statement replaced?
> 1951 if (adev->ip_versions[GC_HWIP][0] == IP_VERSION(10, 3, 0))
> 1952 dmub_asic = DMUB_ASIC_DCN30;
> 1953 else
> 1954 dmub_asic = DMUB_ASIC_DCN30;
> 1955 break;
> 1956 case IP_VERSION(3, 0, 1):
>
> If this is a false positive, please let us know so we can mark it as
> such, or teach the Coverity rules to be smarter. If not, please make
> sure fixes get into linux-next. :) For patches fixing this, please
> include these lines (but double-check the "Fixes" first):
>
> Reported-by: coverity-bot <keescook+coverity-bot@xxxxxxxxxxxx>
> Addresses-Coverity-ID: 1530544 ("Incorrect expression")
> Fixes: a7ab345149b8 ("drm/amd/display: Load DMUB microcode during
> early_init")
>
> Thanks for your attention!
>
> --
> Coverity-bot