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From: Huacai Chen <chenhuacai@kernel.org>
Date: Sun, 12 May 2024 11:11:10 +0800
Message-ID: <CAAhV-H4s_utEOtFDwjPTqxnMWTVjWhmS7bEVRX+t8HK5QDA8Vg@mail.gmail.com>
Subject: Re: [PATCH] LoongArch: Define __ARCH_WANT_NEW_STAT in unistd.h
To: Arnd Bergmann <arnd@arndb.de>
Cc: Huacai Chen <chenhuacai@loongson.cn>, loongarch@lists.linux.dev, 
	Linux-Arch <linux-arch@vger.kernel.org>, Xuefeng Li <lixuefeng@loongson.cn>, 
	guoren <guoren@kernel.org>, WANG Xuerui <kernel@xen0n.name>, 
	Jiaxun Yang <jiaxun.yang@flygoat.com>, linux-kernel@vger.kernel.org, 
	loongson-kernel@lists.loongnix.cn, stable@vger.kernel.org
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On Sat, May 11, 2024 at 11:39=E2=80=AFPM Arnd Bergmann <arnd@arndb.de> wrot=
e:
>
> On Sat, May 11, 2024, at 16:28, Huacai Chen wrote:
> > On Sat, May 11, 2024 at 8:17=E2=80=AFPM Arnd Bergmann <arnd@arndb.de> w=
rote:
>
> >> Importantly, we can't just add fstatat64() on riscv32 because
> >> there is no time64 version for it other than statx(), and I don't
> >> want the architectures to diverge more than necessary.
> >> I would not mind adding a variant of statx() that works for
> >> both riscv32 and loongarch64 though, if it gets added to all
> >> architectures.
> >
> > As far as I know, Ren Guo is trying to implement riscv64 kernel +
> > riscv32 userspace, so I think riscv32 kernel won't be widely used?
>
> I was talking about the ABI, so it doesn't actually matter
> what the kernel is: any userspace ABI without
> CONFIG_COMPAT_32BIT_TIME is equally affected here. On riscv32
> this is the only allowed configuration, while on others (arm32
> or x86-32 userland) you can turn off COMPAT_32BIT_TIME on
> both 32-bit kernel and on 64-bit kernels with compat mode.
I don't know too much detail, but I think riscv32 can do something
similar to arm32 and x86-32, or we can wait for Xuerui to improve
seccomp. But there is no much time for loongarch because the Debian
loong64 port is coming soon.

Huacai

>
>      Arnd
>