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Date: Tue, 2 Sep 2025 09:02:41 +0200
From: Andreas Larsson <andreas@...sler.com>
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Subject: Re: [PATCH v2 3/4] arch: copy_thread: pass clone_flags as u64

On 2025-09-01 15:09, Simon Schuster via B4 Relay wrote:
> From: Simon Schuster <schuster.simon@...mens-energy.com>
> 
> With the introduction of clone3 in commit 7f192e3cd316 ("fork: add
> clone3") the effective bit width of clone_flags on all architectures was
> increased from 32-bit to 64-bit, with a new type of u64 for the flags.
> However, for most consumers of clone_flags the interface was not
> changed from the previous type of unsigned long.
> 
> While this works fine as long as none of the new 64-bit flag bits
> (CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still
> undesirable in terms of the principle of least surprise.
> 
> Thus, this commit fixes all relevant interfaces of the copy_thread
> function that is called from copy_process to consistently pass
> clone_flags as u64, so that no truncation to 32-bit integers occurs on
> 32-bit architectures.
> 
> Signed-off-by: Simon Schuster <schuster.simon@...mens-energy.com>
> ---

Thanks for this and for the whole series! Needed foundation for a
sparc32 clone3 implementation as well.

>  arch/sparc/kernel/process_32.c   | 2 +-
>  arch/sparc/kernel/process_64.c   | 2 +-

Acked-by: Andreas Larsson <andreas@...sler.com> # sparc

Cheers,
Andreas

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