Re: [PATCH 6.12 00/89] 6.12.50-rc1 review

[Guenter Roeck]

On 9/30/25 07:47, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 6.12.50 release.
> There are 89 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Thu, 02 Oct 2025 14:37:59 +0000.
> Anything received after that time might be too late.

s390:allmodconfig:
parisc:allmodconfig:

drivers/gpu/drm/i915/display/intel_backlight.c: In function 'scale':
././include/linux/compiler_types.h:536:45: error:
	call to '__compiletime_assert_666' declared with attribute error: clamp() low limit source_min greater than high limit source_max
include/linux/compiler_types.h:517:25: note: in definition of macro '__compiletime_assert'
  517 |                         prefix ## suffix();                             \
      |                         ^~~~~~
include/linux/compiler_types.h:536:9: note: in expansion of macro '_compiletime_assert'
  536 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
      |         ^~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert'
   39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
      |                                     ^~~~~~~~~~~~~~~~~~
include/linux/minmax.h:188:9: note: in expansion of macro 'BUILD_BUG_ON_MSG'
  188 |         BUILD_BUG_ON_MSG(statically_true(ulo > uhi),                            \
      |         ^~~~~~~~~~~~~~~~
include/linux/minmax.h:195:9: note: in expansion of macro '__clamp_once'
  195 |         __clamp_once(type, val, lo, hi, __UNIQUE_ID(v_), __UNIQUE_ID(l_), __UNIQUE_ID(h_))
      |         ^~~~~~~~~~~~
include/linux/minmax.h:206:28: note: in expansion of macro '__careful_clamp'
  206 | #define clamp(val, lo, hi) __careful_clamp(__auto_type, val, lo, hi)
      |                            ^~~~~~~~~~~~~~~
drivers/gpu/drm/i915/display/intel_backlight.c:47:22: note: in expansion of macro 'clamp'
   47 |         source_val = clamp(source_val, source_min, source_max);

This is exposed by the minmax patch series, as with 6.12.49.

Fixed upstream with commit 6f7150741584 ("drm/i915/backlight: Return immediately
when scale() finds invalid parameters"). This patch also includes an explanation
of what exactly happens (and thanks again to Linus for the analysis).

Guenter