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From: Huacai Chen <chenhuacai@kernel.org>
Date: Sat, 15 Jun 2024 16:52:13 +0800
Message-ID: <CAAhV-H7OR5tkbjj-BPLStneXFr=1DUaFvvh8+a5Bk_jhCAP25Q@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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Hi, Arnd,

On Sun, May 12, 2024 at 3:53=E2=80=AFPM Arnd Bergmann <arnd@arndb.de> wrote=
:
>
> On Sun, May 12, 2024, at 05:11, Huacai Chen wrote:
> > On Sat, May 11, 2024 at 11:39=E2=80=AFPM Arnd Bergmann <arnd@arndb.de> =
wrote:
> >> 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=
> wrote:
> >> 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.
>
> What I meant is that the other architectures only work by
> accident if COMPAT_32BIT_TIME is enabled and statx() gets
> blocked, but then they truncate the timestamps to the tim32
> range, which is not acceptable behavior. Actually mips64 is
> in the same situation because it also only supports 32-bit
> timestamps in newstatat(), despite being a 64-bit
> architecture with a 64-bit time_t in all other syscalls.
We can only wait for the seccomp side to be fixed now? Or we can get
this patch upstream for LoongArch64 at the moment, and wait for
seccomp to fix RISCV32 (and LoongArch32) in future?

Huacai

>
>       Arnd
>