qcom_scm: Incompatible pointer type build failure

[Julien Grall]

Hi Ian,

Thank you for the report.

On 30/04/2019 13:44, Ian Jackson wrote:
> osstest service owner writes ("[linux-4.19 test] 135420: regressions - FAIL"):
> > flight 135420 linux-4.19 real [real]
> > http://logs.test-lab.xenproject.org/osstest/logs/135420/
> >
> > Regressions :-(
> >
> > Tests which did not succeed and are blocking,
> > including tests which could not be run:
> >   build-armhf-pvops             6 kernel-build             fail REGR. vs. 129313
>
> http://logs.test-lab.xenproject.org/osstest/logs/135420/build-armhf-pvops/6.ts-kernel-build.log
>
>    drivers/firmware/qcom_scm.c: In function ÃâËqcom_scm_assign_memÃââ:
>    drivers/firmware/qcom_scm.c:469:47: error: passing argument 3 of ÃâËdma_alloc_coherentÃââ from incompatible pointer type [-Werror=incompatible-pointer-types]
>      ptr = dma_alloc_coherent(__scm->dev, ptr_sz, &ptr_phys, GFP_KERNEL);
>                                                   ^
>    In file included from drivers/firmware/qcom_scm.c:21:0:
>    ./include/linux/dma-mapping.h:560:21: note: expected ÃâËdma_addr_t * {aka long long unsigned int *}Ãââ but argument is of type ÃâËphys_addr_t * {aka unsigned int *}Ãââ
>     static inline void *dma_alloc_coherent(struct device *dev, size_t size,
>                         ^~~~~~~~~~~~~~~~~~
>    cc1: some warnings being treated as errors
>    scripts/Makefile.build:303: recipe for target 'drivers/firmware/qcom_scm.o' failed
>    make[2]: *** [drivers/firmware/qcom_scm.o] Error 1
>    scripts/Makefile.build:544: recipe for target 'drivers/firmware' failed
>    make[1]: *** [drivers/firmware] Error 2
>    make[1]: *** Waiting for unfinished jobs....
>
> I think this build failure is probably a regression; rather it is due
> to the stretch update which brings in a new compiler.

The bug has always been present (and still present in master), it is possible 
the compiler became smarter with the upgrade to stretch.

The problem is similar to [1] and happen when the size of phys_addr_t is 
different to dma_addr_t.

I have CCed the maintainers of this file.

Cheers,

[1] https://lists.xenproject.org/archives/html/xen-devel/2019-04/msg00940.html

--
Julien Grall