Message-ID: <6198f1c8-29b7-dba4-2469-2a99eb03c83e@linaro.org>
Date:   Tue, 28 Feb 2023 13:02:22 +0100
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Subject: Re: [PATCH v2 1/2] MIPS: ebpf jit: Implement DADDI workarounds
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To:     Jiaxun Yang <jiaxun.yang@flygoat.com>, linux-mips@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, tsbogend@alpha.franken.de,
        johan.almbladh@anyfinetworks.com, paulburton@kernel.org,
        bpf@vger.kernel.org
References: <20230228113305.83751-1-jiaxun.yang@flygoat.com>
 <20230228113305.83751-2-jiaxun.yang@flygoat.com>
From:   =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= <philmd@linaro.org>
In-Reply-To: <20230228113305.83751-2-jiaxun.yang@flygoat.com>
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On 28/2/23 12:33, Jiaxun Yang wrote:
> For DADDI errata we just workaround by disable immediate operation
> for BPF_ADD / BPF_SUB to avoid generation of DADDIU.
> 
> All other use cases in JIT won't cause overflow thus they are all safe.
> 
> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
> v2: Drop 64BIT ifdef
> ---
>   arch/mips/Kconfig            | 1 -
>   arch/mips/net/bpf_jit_comp.c | 4 ++++
>   2 files changed, 4 insertions(+), 1 deletion(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>