The section mismatch analysis checks if there are illegal
references from one section to another section.
During linktime or runtime, some sections are dropped;
any use of code/data previously in these sections would
most likely result in an oops.
In the code, functions and variables are annotated with
__init,, etc. (see the full list in include/linux/init.h),
which results in the code/data being placed in specific sections.
The section mismatch analysis is always performed after a full
kernel build, and enabling this option causes the following
additional step to occur:
- Add the option -fno-inline-functions-called-once to gcc commands.
When inlining a function annotated with __init in a non-init
function, we would lose the section information and thus
the analysis would not catch the illegal reference.
This option tells gcc to inline less (but it does result in
a larger kernel).