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From: Andy Lutomirski <luto@amacapital.net>
Date: Mon, 31 Aug 2015 14:00:57 -0700
Message-ID: <CALCETrUUSyfZzQUOya9fLOewehOzm-vkLpPhMriJquFLvSzw6Q@mail.gmail.com>
Subject: Why is irq_stack_union a union?
To: Brian Gerst <brgerst@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        X86 ML <x86@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>, Andi Kleen <andi@firstfloor.org>
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Why not just a struct?

Also, why is this all tangled up in gsbase initialization?  And why
does irq_stack_ptr point 64 bytes from the top?  And why does the
stack overflow thing look STACK_TOP_MARGIN == 128 bytes from the top?

Confused.

--Andy

-- 
Andy Lutomirski
AMA Capital Management, LLC