Re: [PATCH] x86/asm: Fix inline asm call constraints for GCC 4.4

From: Ingo Molnar <mingo@kernel.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	the arch/x86 maintainers <x86@kernel.org>,
	kernel test robot <xiaolong.ye@intel.com>,
	Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Matthias Kaehlcke <mka@chromium.org>,
	Alexander Potapenko <glider@google.com>,
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Dmitriy Vyukov <dvyukov@google.com>,
	Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	LKML <linux-kernel@vger.kernel.org>, LKP <lkp@01.org>
Subject: Re: [PATCH] x86/asm: Fix inline asm call constraints for GCC 4.4
Date: Fri, 29 Sep 2017 10:01:28 +0200	[thread overview]
Message-ID: <20170929080128.eygnwju6rbegs3lh@gmail.com> (raw)
In-Reply-To: <20170929014056.gzfge2efgwfxkokj@treble>

* Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> On Thu, Sep 28, 2017 at 04:53:09PM -0700, Linus Torvalds wrote:
> > On Thu, Sep 28, 2017 at 2:58 PM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> > >
> > > Reported-by: kernel test robot <xiaolong.ye@intel.com>
> > > Fixes: f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang")
> > > Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
> > 
> > Side note: it's not like I personally need the credit, but in general
> > I really want people to pick up on who debugged the code and pointed
> > to the solution. That's often more of the work than the fix itself.
> > 
> > The kernel test robot report looked to be ignored as a "gcc-4.4 is too
> > old to worry about" thing. People who then step up and analyze the
> > problem are rare as it is. They need to be credited in the commit
> > logs.
> > 
> > We don't have any fixed format for that, but it's pretty free-form. So
> > we have tags like
> > 
> >   Root-caused-by:
> >   Diagnosed-by:
> >   Analyzed-by:
> >   Debugged-by:
> >   Bisected-by:
> >   Fix-suggested-by:
> > 
> > etc for giving credit to people who figured out some part of a bug
> > (and, having grepped for this, we also a _shitload_ of miss-spellings
> > of various things ;)
> 
> Indeed, credit is important and I try to give it where it's due.  Sorry
> for the snub!  I anoint you with:
> 
> Debugged-by: Linus Torvalds <torvalds@linux-foundation.org>

When applying the fix I went with:

  Diagnosed-by: Linus Torvalds <torvalds@linux-foundation.org>

Because I think 'diagnosing' a bug is a higher category, which implies debugging. 

( Sometimes we refer to 'debugging a bug' as the reporter adding printks on 
  request and printing out key state that helps understand the bug. It does not 
  necessarily imply root-causing the bug. )

Also note that I added a "Reported-and-Bisected-by:" tag for the ktest robot, to 
further credit the fact that in addition to reporting a kernel crash, a specific 
commit was bisected to as well.

I'll wait for another round of ktest robot testing to make sure the crash is 
indeed fixed.

Thanks,

	Ingo