Re: Please put the gcc "asm goto" bug workaround into stable

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Feb 16, 2024 at 07:57:01AM -0800, Linus Torvalds wrote:
> I didn't think to mark these for stable in the commits, but they
> definitely should go into the stable queue, since it's a known
> mis-compilation of the kvm nested guest code with gcc-11 otherwise.
> 
> The bug technically affects other gcc versions too, but apparently not
> so that we'd actually notice.
> 
> It's two commits:
> 
>   4356e9f841f7 ("work around gcc bugs with 'asm goto' with outputs")
>   68fb3ca0e408 ("update workarounds for gcc "asm goto" issue")
> 
> where the first one works around the problem, and the second one
> ("update") just ends up pinpointing exactly which gcc versions are
> affected so that future gcc releases won't get the unnecessary
> workaround.
> 
> Technically only the first one really needs to go into stable. The
> second one is more of a judgement call - do you want to match
> upstream, and do you care about the (very slight) code generation
> improvement with updated gcc versions?

I've queued both up for 6.6.y and 6.7.y and they took a bit of
hand-holding to get merged.  I gave up at 6.1.y and if anyone wants them
there, I'll gladly take a working backport, but I'm not going to attempt
it.

thanks,

greg k-h