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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
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Subject: Re: [patch V6 36/37] x86/entry: Move paranoid irq tracing out of ASM code
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Date:   Wed, 20 May 2020 17:16:57 +0200
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Andy Lutomirski <luto@kernel.org> writes:

> On Fri, May 15, 2020 at 5:11 PM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> I think something's missing here.  With this patch applied, don't we
> get to exc_debug_kernel() -> handle_debug() without doing
> idtentry_enter() or equivalent?  And that can even enable IRQs.
>
> Maybe exc_debug_kernel() should wrap handle_debug() in some
> appropriate _enter() / _exit() pair?

I'm the one who is missing something here, i.e. the connection of this
patch to #DB. exc_debug_kernel() still looks like this:

	nmi_enter_notrace();
	handle_debug(regs, dr6, false);
	nmi_exit_notrace();

Confused.