Re: [PATCH] dt-bindings: Improve validation build error handling

[Rob Herring]

On Thu, Nov 14, 2019 at 11:59 PM Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> wrote:
>
> On Fri, Nov 15, 2019 at 1:34 AM Rob Herring <robh@xxxxxxxxxx> wrote:
> >
> > On Thu, Nov 14, 2019 at 9:21 AM Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx> wrote:
> > >
> > > On 11/13/2019 2:05 PM, Rob Herring wrote:
> > > > Schema errors can cause make to exit before useful information is
> > > > printed. This leaves developers wondering what's wrong. It can be
> > > > overcome passing '-k' to make, but that's not an obvious solution.
> > > > There's 2 scenarios where this happens.
> > > >
> > > > When using DT_SCHEMA_FILES to validate with a single schema, any error
> > > > in the schema results in processed-schema.yaml being empty causing a
> > > > make error. The result is the specific errors in the schema are never
> > > > shown because processed-schema.yaml is the first target built. Simply
> > > > making processed-schema.yaml last in extra-y ensures the full schema
> > > > validation with detailed error messages happen first.
> > > >
> > > > The 2nd problem is while schema errors are ignored for
> > > > processed-schema.yaml, full validation of the schema still runs in
> > > > parallel and any schema validation errors will still stop the build when
> > > > running validation of dts files. The fix is to not add the schema
> > > > examples to extra-y in this case. This means 'dtbs_check' is no longer a
> > > > superset of 'dt_binding_check'. Update the documentation to make this
> > > > clear.
> > > >
> > > > Cc: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
> > > > Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> > > > Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> > >
> > > I injected a syntax error into a random binding file, and compared the
> > > output with and without this patch.  This patch makes a massive
> > > improvement in giving the user the necessary information to identify and
> > > fix issues.  Thanks!
>
>
> Could you show me an example of the injected syntax error,
> and how this commit will improve the diagnostic?
>
>
> For example, I changed as follows:
>
> diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
> b/Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
> index 47bc1ac36426..358cb1fa4bb6 100644
> --- a/Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
> +++ b/Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
> @@ -89,7 +89,7 @@ required:
>    - clocks
>
>  allOf:
> -  - if:
> +  - if2:
>        properties:
>          compatible:
>            contains:
>
>
>
> The tool clearly explains the cause of the error.
> I am struggling to understand what the current problem is.
>
>
>
> masahiro@pug:~/ref/linux$ make -j8  ARCH=arm  dt_binding_check

Before this patch, you should see processed-schema.yaml built first.
Clean your tree and do:

make -j8  ARCH=arm
DT_SCHEMA_FILES=Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
dt_binding_check

Building processed-schema.yaml will fail because it will be empty as
the 1 file included had an error.

>   CHKDT   Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml
>   DTC     Documentation/devicetree/bindings/arm/altera.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/nxp/lpc32xx.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/pmu.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/rockchip.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/primecell.example.dt.yaml
>   DTC     Documentation/devicetree/bindings/arm/renesas.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/nxp/lpc32xx.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/pmu.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/altera.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/rockchip.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/primecell.example.dt.yaml
>   CHECK   Documentation/devicetree/bindings/arm/renesas.example.dt.yaml
> /home/masahiro/ref/linux/Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml:
> allOf:0: 'if2' is not one of ['$ref', 'if', 'then', 'else']
> make[1]: *** [Documentation/devicetree/bindings/Makefile;12:
> Documentation/devicetree/bindings/gpu/arm,mali-midgard.example.dts]
> Error 1
> make[1]: *** Waiting for unfinished jobs....
> make: *** [Makefile;1266: dt_binding_check] Error 2
>
>
>
>
>
>
> > BTW, update dtschema and you'll get better (or more at least) messages
> > when 'is not valid under any of the given schemas' errors occur.
> >
> > > Tested-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
> >
> > Thanks.
> >
> > Rob
>
>
>
> --
> Best Regards
> Masahiro Yamada