Re: [PATCH -rc 0/4] Protect from GCC garbage input in GCOV

Leon Romanovsky
2020-09-02T17:52:50Z

On Wed, Sep 02, 2020 at 10:42:55AM -0700, Linus Torvalds wrote:
> On Wed, Sep 2, 2020 at 1:55 AM Leon Romanovsky <leon@kernel.org> wrote:
> >
> > Bottom line, GCOV is broken on GCC 10.2.
>
> The patches don't really make sense to me.
>
> How about we just disable GCOV with the known-broken compiler version
> instead? As mentioned in the replies to individual patches, it looks
> like the "fixes" are random bandaids that don't _really_ fix anything.

Right, as I wrote in RFC "solution is wrong", I knew it, just didn't
get any feedback on how to do it correctly.

Are you suggesting something like this?

diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 3110c77230c7..bc0e355f64aa 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -3,7 +3,7 @@ menu "GCOV-based kernel profiling"

config GCOV_KERNEL
bool "Enable gcov-based kernel profiling"
- depends on DEBUG_FS
+ depends on DEBUG_FS && (GCC_VERSION >= XXX && GCC_VERSION < YYY)
select CONSTRUCTORS if !UML
default n
help
~

Thanks

>
> Linus