Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack

From	Josh Poimboeuf <jpoimboe@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack
Date	2016-08-15 17:50 +0200
Message-ID	<s6sjg-7pG-27@gated-at.bofh.it> (permalink)
References	<s5lMR-2Ra-3@gated-at.bofh.it> <s5lMS-2Ra-19@gated-at.bofh.it> <s5ZAC-5TR-25@gated-at.bofh.it>
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On Sun, Aug 14, 2016 at 12:52:40AM -0700, Andy Lutomirski wrote:
> On Fri, Aug 12, 2016 at 7:29 AM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> > There has been a 64-byte gap at the end of the irq stack for at least 12
> > years.  It predates git history, and I can't find any good reason for
> > it.  Remove it.  What's the worst that could happen?
> 
> I can't think of any reason this would matter.
> 
> For that matter, do you have any idea why irq_stack_union is a union
> or why we insist on sticking it at %gs:0?  Sure, the *canary* needs to
> live at a fixed offset (because GCC is daft, sigh), but I don't see
> what that has to do with the rest of the IRQ stack.

Good question.  I have no idea...

-- 
Josh

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[PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-08-12 16:40 +0200
  Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack Andy Lutomirski <luto@amacapital.net> - 2016-08-14 11:10 +0200
    Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack Brian Gerst <brgerst@gmail.com> - 2016-08-14 15:00 +0200
      Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-08-15 19:10 +0200
    Re: [PATCH v3 45/51] x86: remove 64-byte gap at end of irq stack Josh Poimboeuf <jpoimboe@redhat.com> - 2016-08-15 17:50 +0200

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