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Date:   Fri, 30 Nov 2018 22:13:42 +0100 (CET)
From:   Jiri Kosina <jikos@kernel.org>
To:     Andy Lutomirski <luto@kernel.org>
cc:     Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, X86 ML <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Jason Baron <jbaron@akamai.com>,
        David Laight <David.Laight@aculab.com>,
        Borislav Petkov <bp@alien8.de>, julia@ni.com, jeyu@kernel.org,
        "H. 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 Fri, 30 Nov 2018, Andy Lutomirski wrote:

> According to the SDM, you can program the APIC ICR to request an SMI. 
> It's not remotely clear to me what will happen if we do this.  

I think one of the known reliable ways to trigger SMI is to write 0x0 to 
the SMI command I/O port (0xb2).

> For all I know, the SMI handler will explode and the computer will catch 
> fire.

Ha, therefore noone can't claim any more that SMIs are always harmful :)

-- 
Jiri Kosina
SUSE Labs