* David Woodhouse <dw...@infradead.org> wrote:
> The exception handler already returns if the exception was int3, but
> not for anything else. Less so the "print something warm and fuzzy"
> part; it just does the same register dump. But we could change that.
>
> I'm less keen on making it unconditional though. Kexec is a
> performance-critical path when every millisecond is perceived as
> guest steal time, and the serial output should only happen in
> production if something goes *wrong*.
>
> And besides, most kexec users don't have early_printk enabled anyway
> so if we break them, this idea doesn't help.
So this check would only cause any real overhead if serial debugging is
enabled - in which case there's already substantial overhead due to the
serial console overhead (virtual or otherwise).
As to not printing anything unless the early serial console is enabled
- that's fine, we'd still *break* if something doesn't work in this
code path, so at least the exception handling machinery is kept
well-tested. :-)
Thanks,
Ingo
