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Date:   Fri, 16 Oct 2020 11:37:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     hpa@zytor.com
Cc:     Ian Rogers <irogers@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, Masami Hiramatsu <mhiramat@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        linux-kernel@vger.kernel.org,
        Adrian Hunter <adrian.hunter@intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Numfor Mbiziwo-Tiapo <nums@google.com>
Subject: Re: [PATCH v2] x86/insn, tools/x86: Fix some potential undefined
 behavior.
Message-ID: <20201016093724.GH2611@hirez.programming.kicks-ass.net>
References: <20201015161216.1563600-1-irogers@google.com>
 <5E711F64-A9BF-48EC-83A3-3C644D80F848@zytor.com>
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On Thu, Oct 15, 2020 at 02:34:57PM -0700, hpa@zytor.com wrote:
> Wait, what?
> 
> You are taking about x86-specific code, and on x86 unaligned memory
> accesses are supported, well-defined, and ubiquitous. 

Objtool uses this x86 instruction decoder, people are cross-buildling
objtool to cross-build x86 kernels.

So it's entirely possible to run the x86 insn decode on BE RISC, which
very much doesn't like unaligned loads.