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Subject: Re: [PATCH v4 0/4] LoongArch: Support new relocation types
To:     Xi Ruoyao <xry111@xry111.site>, loongarch@lists.linux.dev
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Cc:     linux-kernel@vger.kernel.org, WANG Xuerui <kernel@xen0n.name>,
        Huacai Chen <chenhuacai@kernel.org>,
        Jinyang He <hejinyang@loongson.cn>,
        Lulu Cheng <chenglulu@loongson.cn>
From:   Youling Tang <tangyouling@loongson.cn>
Message-ID: <d7670b60-2782-4642-995b-7baa01779a66@loongson.cn>
Date:   Fri, 29 Jul 2022 20:19:56 +0800
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On 07/29/2022 07:45 PM, Xi Ruoyao wrote:
> On Fri, 2022-07-29 at 18:36 +0800, Xi Ruoyao wrote:
>
>> The relocation against local percpu variable is broken up.  I'll try
>> to fix it.
>
> Hmm... The problem is the "addresses" of per-cpu symbols are faked: they
> are actually offsets from $r21.  So we can't just load such an offset
> with PCALA addressing.
>
> It looks like we'll need to introduce an attribute for GCC to make an
> variable "must be addressed via GOT", and add the attribute into
> PER_CPU_ATTRIBUTES.
Yes, we need a GCC attribute to specify the per-cpu variable.

Thanks,
Youling
>