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From:   Andy Lutomirski <luto@kernel.org>
Date:   Fri, 8 May 2020 17:44:25 -0700
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Subject: Re: [patch V4 part 3 04/29] x86/traps: Make interrupt enable/disable
 symmetric in C code
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Joel Fernandes <joel@joelfernandes.org>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>,
        Brian Gerst <brgerst@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Will Deacon <will@kernel.org>
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On Tue, May 5, 2020 at 7:15 AM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> Traps enable interrupts conditionally but rely on the ASM return code to
> disable them again. That results in redundant interrupt disable and trace
> calls.
>
> Make the trap handlers disable interrupts before returning to avoid that,
> which allows simplification of the ASM entry code.

Acked-by: Andy Lutomirski <luto@kernel.org>

And thanks!  This has bothered me forever.