Re: gcc-10: kernel stack is corrupted and fails to boot

[Arvind Sankar]

On Thu, May 14, 2020 at 12:20:38AM +0200, Borislav Petkov wrote:
> On Wed, May 13, 2020 at 11:49:49PM +0200, Arnd Bergmann wrote:
> > Right, in particular since Linus started building with gcc-10 already and
> > would likely soon run into that problem if he hasn't already ;-)
> 
> Oh noo, we don't want Linus' kernel broken. ;-)
> 
> We will send him the fix this weekend.
> 
> Looking at that branch:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/log/?h=x86/build
> 
> I think we can send the whole thing even.
> 
> Linus, shout if you'd prefer only the last three commits there:
> 
> 950a37078aa0 x86/build: Use $(CONFIG_SHELL)
> f670269a42bf x86: Fix early boot crash on gcc-10, next try
> 73da86741e7f x86/build: Check whether the compiler is sane
> 
> but the other three from Masahiro are simple cleanups:
> 
> 675a59b7dec6 x86/boot/build: Add phony targets in arch/x86/boot/Makefile to PHONY
> 30ce434e44d7 x86/boot/build: Make 'make bzlilo' not depend on vmlinux or $(obj)/bzImage
> e3c7c1052271 x86/boot/build: Add cpustr.h to targets and remove clean-files
> 
> which should be ok to take now too AFAICT.
> 
> Thx.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> SUSE Software Solutions Germany GmbH, GF: Felix ImendÃrffer, HRB 36809, AG NÃrnberg

I notice that doesn't add it to start_kernel (init/main.c). That's not
currently affected, but I think we should it add for consistency and
future-proofing, at least for 5.8?