Re: [PATCH rdma-next 3/4] gcov: Protect from uninitialized number of functions provided by GCC 10.2

From: Linus Torvalds
Date: Wed Sep 02 2020 - 13:41:49 EST


On Wed, Sep 2, 2020 at 1:55 AM Leon Romanovsky <leon@xxxxxxxxxx> wrote:
>
> This trace is seen because n_function value provided by GCC through
> __gcov_init() is ridiculously high, in my case it was 2698213824,
> which probably means that the field is not initialized.

This seems to be wrong - since a different (smaller) uninitialized
value will succeed in the kcalloc, but will then walk some random
array size when copying and fail later instead.

So this doesn't actually seem to _fix_ anything, it just hides one
special case of bogus values.

Linus