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Date:   Tue, 12 May 2020 21:51:08 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Petr Mladek <pmladek@suse.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>,
        Brian Gerst <brgerst@gmail.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Will Deacon <will@kernel.org>
Subject: Re: [patch V4 part 3 01/29] x86/traps: Mark fixup_bad_iret()
 noinstr
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On Fri, 8 May 2020 17:39:00 -0700
Andy Lutomirski <luto@kernel.org> wrote:

> On Tue, May 5, 2020 at 7:15 AM Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > This is called from deep entry ASM in a situation where instrumentation
> > will cause more harm than providing useful information.
> >  
> 
> Acked-by: Andy Lutomirski <luto@kernel.org>
> 
> Maybe add to changelog:
> 
> Switch from memmove() to memcpy() because memmove() can't be called
> from noinstr code.

Yes please, because I was about to say that there was changes that
didn't seem to fit the change log.

I would also add a comment in the code saying that we need the temp
variable to use memcpy as memmove can't be used in noinstr code.

-- Steve