[PATCH v2 11/11] kexec_file: Move purgatories sha256 to common code

The code to verify the new kernels sha digest is applicable for all architectures. Move it to common code. One problem is the string.c implementation on x86. Currently sha256 includes x86/boot/string.h which defines memcpy and memset to be gcc builtins. By moving the sha256 implementation to

[PATCH v2 11/11] kexec_file: Move purgatories sha256 to common code

The code to verify the new kernels sha digest is applicable for all architectures. Move it to common code. One problem is the string.c implementation on x86. Currently sha256 includes x86/boot/string.h which defines memcpy and memset to be gcc builtins. By moving the sha256 implementation to