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Date:   Thu, 29 Nov 2018 18:35:26 +0100 (CET)
From:   Jiri Kosina <jikos@kernel.org>
To:     Andy Lutomirski <luto@amacapital.net>
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        Linus Torvalds <torvalds@linux-foundation.org>,
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        Ingo Molnar <mingo@kernel.org>,
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        julia@ni.com, jeyu@kernel.org, Peter Anvin <hpa@zytor.com>
Subject: Re: [PATCH v2 4/4] x86/static_call: Add inline static call implementation
 for x86-64
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On Thu, 29 Nov 2018, Andy Lutomirski wrote:

> Does anyone know what the actual hardware semantics are?  The SDM is not 
> particularly informative unless I looked at the wrong section.

I don't think SDM answers all the questions there, unfortunately.

I vaguely remember that back then when I was preparing the original 
text_poke_bp() implementation, hpa had to provide some answers directly 
from inner depths of Intel ... see fd4363fff3 ("x86: Introduce int3 
(breakpoint)-based instruction patching") for reference.

-- 
Jiri Kosina
SUSE Labs