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Date:   Fri, 4 Mar 2022 09:57:33 -0800
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com,
        andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org,
        ndesaulniers@google.com, keescook@chromium.org,
        samitolvanen@google.com, mark.rutland@arm.com,
        alyssa.milburn@intel.com, mbenes@suse.cz, rostedt@goodmis.org,
        mhiramat@kernel.org, alexei.starovoitov@gmail.com
Subject: Re: [PATCH v3 22/39] x86/ibt: Add IBT feature, MSR and #CP handling
Message-ID: <20220304175733.zoik2fqpizygnlq7@treble>
References: <20220303112321.422525803@infradead.org>
 <20220303112826.299051388@infradead.org>
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On Thu, Mar 03, 2022 at 12:23:43PM +0100, Peter Zijlstra wrote:
> +bool ibt_selftest(void)
> +{
> +	unsigned long ret;
> +
> +	asm ("	lea ibt_selftest_ip(%%rip), %%rax\n\t"
> +	     ANNOTATE_RETPOLINE_SAFE
> +	     "	jmp *%%rax\n\t"
> +	     ASM_REACHABLE
> +	     ANNOTATE_NOENDBR
> +	     "ibt_selftest_ip: nop\n\t"

Maybe pedantic, but I find the annotations to be less surprising if they
come after the label:

	"ibt_selftest_ip:\n\t"
	ASM_REACHABLE
	ANNOTATE_NOENDBR
	"nop\n\t"

-- 
Josh