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Date:   Thu, 3 Dec 2020 17:54:20 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Tom Lendacky <thomas.lendacky@amd.com>
Cc:     Masami Hiramatsu <mhiramat@kernel.org>, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        "H . Peter Anvin" <hpa@zytor.com>, Joerg Roedel <jroedel@suse.de>,
        "Gustavo A . R . Silva" <gustavoars@kernel.org>,
        Jann Horn <jannh@google.com>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Ricardo Neri <ricardo.neri-calderon@linux.intel.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] x86/uprobes: Fix not using prefixes.nbytes for
 loop over prefixes.bytes
Message-ID: <20201203165420.GL3059@zn.tnic>
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 <20201203124121.GI3059@zn.tnic>
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On Thu, Dec 03, 2020 at 10:45:48AM -0600, Tom Lendacky wrote:
> Since this is based on the array size, can
> 
> 	idx < NUM_LEGACY_PREFIXES
> 
> be replaced with:
> 
> 	idx < ARRAY_SIZE(insn->prefixes.bytes)

Actually, this needs another change:

struct insn_field {
        union {
                insn_value_t value;
                insn_byte_t bytes[NUM_LEGACY_PREFIXES];

because you can have max. 4 legacy prefixes and then we can do either of
the checks above.

Mine is shorter tho. :-)

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette