Re: [GIT pull] perf/urgent for 5.7-rc2

[Peter Zijlstra]

On Mon, Apr 20, 2020 at 01:17:30PM -0500, Josh Poimboeuf wrote:
> On Mon, Apr 20, 2020 at 07:40:31PM +0200, Peter Zijlstra wrote:

> > So my pet peeve is that when objtool errors, or crashes, the .o file
> > gets deleted and it becomes really hard to debug the situation. I'm
> > thinking that your suggestion would actually help with that too.
> 
> I do have the same pet peeve and I'm thinking we should just revert
> 644592d32837 ("objtool: Fail the kernel build on fatal errors") which
> would ease most of the pain.  Those fatal errors don't really buy us
> much IMO.  Agree?

Well, I like that it stops the kernel build on an error; I hate that it
makes it so damn hard to then diagnose and fix the error :/

Also, it doesn't really help for crashes, luckily those are somewhat
rare -- except I had one today as a result of a mis-merge...

> > I just don't have enough Kbuild foo to even attempt this :/
> 
> It's an interesting idea, but it might have its own share of annoyances.
> 
> If you added something bad to a file, and just rebuilt that file, you
> wouldn't see the objtool warning until later when you build the entire
> kernel. 

Moo.. :/