linux-next: build failure after merge of the drm tree

[Nathan Chancellor]

On Mon, Jul 01, 2024 at 07:13:19PM +1000, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the drm tree, today's linux-next build (powerpc
> allyesconfig) failed like this:
> 
> In file included from arch/powerpc/include/asm/mmu.h:144,
>                  from arch/powerpc/include/asm/paca.h:18,
>                  from arch/powerpc/include/asm/current.h:13,
>                  from include/linux/sched.h:12,
>                  from include/linux/ratelimit.h:6,
>                  from include/linux/dev_printk.h:16,
>                  from include/linux/device.h:15,
>                  from include/linux/dma-mapping.h:8,
>                  from drivers/gpu/drm/omapdrm/omap_gem.c:7:
> drivers/gpu/drm/omapdrm/omap_gem.c: In function 'omap_gem_pin_tiler':
> arch/powerpc/include/asm/page.h:25:33: error: conversion from 'long unsigned int' to 'u16' {aka 'short unsigned int'} changes value from '65536' to '0' [-Werror=overflow]
>    25 | #define PAGE_SIZE               (ASM_CONST(1) << PAGE_SHIFT)
>       |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/omapdrm/omap_gem.c:758:42: note: in expansion of macro 'PAGE_SIZE'
>   758 |                                          PAGE_SIZE);
>       |                                          ^~~~~~~~~
> drivers/gpu/drm/omapdrm/omap_gem.c: In function 'omap_gem_init':
> arch/powerpc/include/asm/page.h:25:33: error: conversion from 'long unsigned int' to 'u16' {aka 'short unsigned int'} changes value from '65536' to '0' [-Werror=overflow]
>    25 | #define PAGE_SIZE               (ASM_CONST(1) << PAGE_SHIFT)
>       |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/omapdrm/omap_gem.c:1504:65: note: in expansion of macro 'PAGE_SIZE'
>  1504 |                         block = tiler_reserve_2d(fmts[i], w, h, PAGE_SIZE);
>       |                                                                 ^~~~~~~~~
> cc1: all warnings being treated as errors
> 
> Exposed by commit
> 
>   dc6fcaaba5a5 ("drm/omap: Allow build with COMPILE_TEST=y")
> 
> PowerPC 64 bit uses 64k pages.
> 
> I have reverted that commit for today.

FWIW, I sent a patch to address this in a bit of a more targeted manner
over a week ago:

https://lore.kernel.org/20240620-omapdrm-restrict-compile-test-to-sub-64kb-page-size-v1-1-5e56de71ffca@kernel.org/

Although somehow, I left off Ville from that patch :/

Cheers,
Nathan