Re: [PATCH v2 4/4] x86/static_call: Add inline static call implementation for x86-64

From: Jiri Kosina
Date: Thu Nov 29 2018 - 12:35:35 EST


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