[SEVERE] Re: [REGRESSION] Linux kernel 6.12.75 fails to compile with -Werror=implicit-function-declaration

[Aditya Garg]

Looks like kernel 6.12, 6.6 and 6.1 series got only one part of the three patches sent, thus causing this regression.

Marking this as SEVERE, please forgive me if I did wrong.

> On 4 Mar 2026, at 11:05 PM, Aditya Garg <gargaditya08@xxxxxxxx> wrote:
> 
> Hi
> 
> I found out that Linux kernel 6.12.75 failed to compiled in my automatic builds. The compiler throws the error:
> 
> arch/x86/kernel/setup.c: In function 'ima_get_kexec_buffer':
> arch/x86/kernel/setup.c:380:15: error: implicit declaration of function 'ima_validate_range' [-Werror=implicit-function-declaration]
> 380 |         ret = ima_validate_range(ima_kexec_buffer_phys, ima_kexec_buffer_size);
>    |               ^~~~~~~~~~~~~~~~~~
> cc1: some warnings being treated as errors
> make[7]: *** [scripts/Makefile.build:229: arch/x86/kernel/setup.o] Error 1
> make[6]: *** [scripts/Makefile.build:466: arch/x86/kernel] Error 2
> make[5]: *** [scripts/Makefile.build:466: arch/x86] Error 2
> 
> Upon searching a bit, I found out that failure of this patch to be backported seems to be main reason:
> 
> https://lore.kernel.org/all/20251231061609.907170-2-harshit.m.mogalapalli@xxxxxxxxxx/
> 
> Looks like this series itself was not properly backported.
> 
> I am not sure if any other kernel version is affected. I currently build 6.19 and 6.12 series for my use.
> 
> Thanks!
> Aditya