drm/amd/pm: fix error handling

[PATCH] drm/amd/pm: fix error handling

Posted by trix@redhat.com 4 years, 4 months ago

From: Tom Rix <trix@redhat.com>

clang static analysis reports this error
amdgpu_smu.c:2289:9: warning: Called function pointer
  is null (null dereference)
        return smu->ppt_funcs->emit_clk_levels(
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There is a logic error in the earlier check of
emit_clk_levels.  The error value is set to
the ret variable but ret is never used.  Return
directly and remove the unneeded ret variable.

Fixes: 5d64f9bbb628 ("amdgpu/pm: Implement new API function "emit" that accepts buffer base and write offset")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
index af368aa1fd0ae..5f3b3745a9b7a 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
@@ -2274,7 +2274,6 @@ static int smu_emit_ppclk_levels(void *handle, enum pp_clock_type type, char *bu
 {
 	struct smu_context *smu = handle;
 	enum smu_clk_type clk_type;
-	int ret = 0;
 
 	clk_type = smu_convert_to_smuclk(type);
 	if (clk_type == SMU_CLK_COUNT)
@@ -2284,7 +2283,7 @@ static int smu_emit_ppclk_levels(void *handle, enum pp_clock_type type, char *bu
 		return -EOPNOTSUPP;
 
 	if (!smu->ppt_funcs->emit_clk_levels)
-		ret = -ENOENT;
+		return -ENOENT;
 
 	return smu->ppt_funcs->emit_clk_levels(smu, clk_type, buf, offset);
 
-- 
2.26.3

RE: [PATCH] drm/amd/pm: fix error handling

Posted by Quan, Evan 4 years, 4 months ago

[AMD Official Use Only]

Reviewed-by: Evan Quan <evan.quan@amd.com>

> -----Original Message-----
> From: trix@redhat.com <trix@redhat.com>
> Sent: Saturday, February 5, 2022 11:00 PM
> To: Quan, Evan <Evan.Quan@amd.com>; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Koenig, Christian
> <Christian.Koenig@amd.com>; Pan, Xinhui <Xinhui.Pan@amd.com>;
> airlied@linux.ie; daniel@ffwll.ch; nathan@kernel.org;
> ndesaulniers@google.com; Lazar, Lijo <Lijo.Lazar@amd.com>; Powell, Darren
> <Darren.Powell@amd.com>; Chen, Guchun <Guchun.Chen@amd.com>;
> Grodzovsky, Andrey <Andrey.Grodzovsky@amd.com>
> Cc: amd-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; linux-
> kernel@vger.kernel.org; llvm@lists.linux.dev; Tom Rix <trix@redhat.com>
> Subject: [PATCH] drm/amd/pm: fix error handling
> 
> From: Tom Rix <trix@redhat.com>
> 
> clang static analysis reports this error
> amdgpu_smu.c:2289:9: warning: Called function pointer
>   is null (null dereference)
>         return smu->ppt_funcs->emit_clk_levels(
>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> There is a logic error in the earlier check of
> emit_clk_levels.  The error value is set to
> the ret variable but ret is never used.  Return
> directly and remove the unneeded ret variable.
> 
> Fixes: 5d64f9bbb628 ("amdgpu/pm: Implement new API function "emit" that
> accepts buffer base and write offset")
> Signed-off-by: Tom Rix <trix@redhat.com>
> ---
>  drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> index af368aa1fd0ae..5f3b3745a9b7a 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> @@ -2274,7 +2274,6 @@ static int smu_emit_ppclk_levels(void *handle,
> enum pp_clock_type type, char *bu
>  {
>  	struct smu_context *smu = handle;
>  	enum smu_clk_type clk_type;
> -	int ret = 0;
> 
>  	clk_type = smu_convert_to_smuclk(type);
>  	if (clk_type == SMU_CLK_COUNT)
> @@ -2284,7 +2283,7 @@ static int smu_emit_ppclk_levels(void *handle,
> enum pp_clock_type type, char *bu
>  		return -EOPNOTSUPP;
> 
>  	if (!smu->ppt_funcs->emit_clk_levels)
> -		ret = -ENOENT;
> +		return -ENOENT;
> 
>  	return smu->ppt_funcs->emit_clk_levels(smu, clk_type, buf, offset);
> 
> --
> 2.26.3

Re: [PATCH] drm/amd/pm: fix error handling

Posted by Alex Deucher 4 years, 4 months ago

Applied.  Thanks!

Alex

On Sun, Feb 6, 2022 at 10:04 PM Quan, Evan <Evan.Quan@amd.com> wrote:
>
> [AMD Official Use Only]
>
> Reviewed-by: Evan Quan <evan.quan@amd.com>
>
> > -----Original Message-----
> > From: trix@redhat.com <trix@redhat.com>
> > Sent: Saturday, February 5, 2022 11:00 PM
> > To: Quan, Evan <Evan.Quan@amd.com>; Deucher, Alexander
> > <Alexander.Deucher@amd.com>; Koenig, Christian
> > <Christian.Koenig@amd.com>; Pan, Xinhui <Xinhui.Pan@amd.com>;
> > airlied@linux.ie; daniel@ffwll.ch; nathan@kernel.org;
> > ndesaulniers@google.com; Lazar, Lijo <Lijo.Lazar@amd.com>; Powell, Darren
> > <Darren.Powell@amd.com>; Chen, Guchun <Guchun.Chen@amd.com>;
> > Grodzovsky, Andrey <Andrey.Grodzovsky@amd.com>
> > Cc: amd-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; linux-
> > kernel@vger.kernel.org; llvm@lists.linux.dev; Tom Rix <trix@redhat.com>
> > Subject: [PATCH] drm/amd/pm: fix error handling
> >
> > From: Tom Rix <trix@redhat.com>
> >
> > clang static analysis reports this error
> > amdgpu_smu.c:2289:9: warning: Called function pointer
> >   is null (null dereference)
> >         return smu->ppt_funcs->emit_clk_levels(
> >                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > There is a logic error in the earlier check of
> > emit_clk_levels.  The error value is set to
> > the ret variable but ret is never used.  Return
> > directly and remove the unneeded ret variable.
> >
> > Fixes: 5d64f9bbb628 ("amdgpu/pm: Implement new API function "emit" that
> > accepts buffer base and write offset")
> > Signed-off-by: Tom Rix <trix@redhat.com>
> > ---
> >  drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > index af368aa1fd0ae..5f3b3745a9b7a 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > @@ -2274,7 +2274,6 @@ static int smu_emit_ppclk_levels(void *handle,
> > enum pp_clock_type type, char *bu
> >  {
> >       struct smu_context *smu = handle;
> >       enum smu_clk_type clk_type;
> > -     int ret = 0;
> >
> >       clk_type = smu_convert_to_smuclk(type);
> >       if (clk_type == SMU_CLK_COUNT)
> > @@ -2284,7 +2283,7 @@ static int smu_emit_ppclk_levels(void *handle,
> > enum pp_clock_type type, char *bu
> >               return -EOPNOTSUPP;
> >
> >       if (!smu->ppt_funcs->emit_clk_levels)
> > -             ret = -ENOENT;
> > +             return -ENOENT;
> >
> >       return smu->ppt_funcs->emit_clk_levels(smu, clk_type, buf, offset);
> >
> > --
> > 2.26.3