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From:   Huacai Chen <chenhuacai@kernel.org>
Date:   Mon, 1 Aug 2022 20:09:39 +0800
Message-ID: <CAAhV-H7pWc2bNtdyoczmANiNLSs_+A1ZVhakMdrZjGFXpMzCfQ@mail.gmail.com>
Subject: Re: [PATCH v4 0/4] LoongArch: Support new relocation types
To:     Xi Ruoyao <xry111@xry111.site>
Cc:     Youling Tang <tangyouling@loongson.cn>,
        Jinyang He <hejinyang@loongson.cn>, loongarch@lists.linux.dev,
        LKML <linux-kernel@vger.kernel.org>,
        WANG Xuerui <kernel@xen0n.name>,
        Lulu Cheng <chenglulu@loongson.cn>
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Hi, Ruoyao,

On Mon, Aug 1, 2022 at 7:40 PM Xi Ruoyao <xry111@xry111.site> wrote:
>
> On Mon, 2022-08-01 at 19:28 +0800, Youling Tang wrote:
>
> > > Actually, I really hope kernel image is in the XKVRANGE, rather
> > > than being in XKPRANGE. So that we can limit kernel and modules
> > > be in 4GB range. I think it will make all work normally. :-(
> > >
> >
> > Assuming that the kernel and modules are limited to 4G, the external
> > symbols will be accessed through pcrel32, which means that there is no
> > need to pass the GOT table entry and there is no need for got support
>
> We'll still need to modify GCC to use PC-rel for accessing an object in
> another TU (by default, or an option to control), instead of GOT.  Or
> just add support to GOT relocations here.  But anyway it will be much
> easier as we won't need to handle per-CPU variables specially.
All tlb-mapped kernel may be supported in future, but no now. Because
there are a ton of problems. :)

Huacai
> --
> Xi Ruoyao <xry111@xry111.site>
> School of Aerospace Science and Technology, Xidian University