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Date:   Fri, 29 Apr 2022 13:09:05 -0700
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Chen Zhongjin <chenzhongjin@huawei.com>,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-arch@vger.kernel.org, jthierry@redhat.com,
        catalin.marinas@arm.com, will@kernel.org, masahiroy@kernel.org,
        ycote@redhat.com, herbert@gondor.apana.org.au,
        mark.rutland@arm.com, davem@davemloft.net, ardb@kernel.org,
        maz@kernel.org, tglx@linutronix.de, luc.vanoostenryck@gmail.com
Subject: Re: [RFC PATCH v4 25/37] arm64: bpf: Skip validation of
 ___bpf_prog_run
Message-ID: <20220429200905.yjwxorrkd4u5rdmn@treble>
References: <20220429094355.122389-1-chenzhongjin@huawei.com>
 <20220429094355.122389-26-chenzhongjin@huawei.com>
 <YmvIZG5Ke6vElb/e@hirez.programming.kicks-ass.net>
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On Fri, Apr 29, 2022 at 01:13:40PM +0200, Peter Zijlstra wrote:
> On Fri, Apr 29, 2022 at 05:43:43PM +0800, Chen Zhongjin wrote:
> > There is a jump table encoded in ___bpf_prog_run and objtool-arm64
> > can't deal with it now. Skip validate it for arm64.
> 
> But, but, but, an earlier patch did -fno-jump-tables!

IIRC, -fno-jump-tables is specific to switch statements but this
function has a C-implemented jump table.

-- 
Josh