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Date:   Thu, 10 Jan 2019 13:24:09 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Sean Christopherson <sean.j.christopherson@intel.com>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        Nadav Amit <namit@vmware.com>, X86 ML <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Jason Baron <jbaron@akamai.com>, Jiri Kosina <jkosina@suse.cz>,
        David Laight <David.Laight@ACULAB.COM>,
        Borislav Petkov <bp@alien8.de>,
        Julia Cartwright <julia@ni.com>, Jessica Yu <jeyu@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Edward Cree <ecree@solarflare.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>
Subject: Re: [PATCH v3 5/6] x86/alternative: Use a single access in
 text_poke() where possible
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On Thu, 10 Jan 2019 10:04:28 -0800
Sean Christopherson <sean.j.christopherson@intel.com> wrote:

> > What atomicity guarantee does the above require?  
> 
> I was asking in the context of static calls.  My understanding is that
> the write to change the imm32 of the CALL needs to be atomic from a
> code fetch perspective so that we don't jump to a junk address.
> 
> Or were you saying that Intel gave an official OK on text_poke_bp()?

Yes, the latter. I was talking about Intel giving the official OK for
text_poke_bp().

-- Steve