Re: [RFC PATCH 2/2] bpf: Initialise mod[] in bpf_trace_printk

From: David Miller
Date: Tue Aug 08 2017 - 17:54:42 EST


From: James Hogan <james.hogan@xxxxxxxxxx>
Date: Tue, 08 Aug 2017 22:20:05 +0100

> cool, i hadn't realised unmentioned elements in an initialiser are
> always zeroed, even when non-global/static, so had interpreted the
> whole array as uninitialised. learn something new every day :-)
> sorry for the noise.

You didn't have to know in the first place, you could have simply
compiled the code into assembler by running:

make kernel/trace/bpf_trace.s

and seen for yourself before putting all of this time and effort into
this patch and discussion.

If you don't know what the compiler does, simply look!