Message-ID: <1513293754.18523.287.camel@codethink.co.uk>
Subject: Re: [Y2038] [PATCH v2 04/10] arch: introduce CONFIG_64BIT_TIME
From: Ben Hutchings <ben.hutchings@codethink.co.uk>
To: Deepa Dinamani <deepa.kernel@gmail.com>, tglx@linutronix.de,
        john.stultz@linaro.org
Cc: y2038@lists.linaro.org, linux-kernel@vger.kernel.org, arnd@arndb.de
Date: Thu, 14 Dec 2017 23:22:34 +0000
In-Reply-To: <20171127193037.8711-5-deepa.kernel@gmail.com>
References: <20171127193037.8711-1-deepa.kernel@gmail.com>
         <20171127193037.8711-5-deepa.kernel@gmail.com>
Organization: Codethink Ltd.
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On Mon, 2017-11-27 at 11:30 -0800, Deepa Dinamani wrote:
> There are a total of 53 system calls (aside from ioctl) that pass a time_t
> or derived data structure as an argument, and in order to extend time_t
> to 64-bit, we have to replace them with new system calls and keep providing
> backwards compatibility.
> 
> To avoid adding completely new and untested code for this purpose, we
> introduce a new CONFIG_64BIT_TIME symbol. Every architecture that supports
> new 64 bit time_t syscalls enables this config via ARCH_HAS_64BIT_TIME.
> 
> After this is done for all architectures, the CONFIG_64BIT_TIME symbol
> will be deleted.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
> ---
>  arch/Kconfig | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 4f03534bfa6b..11810c29c1fa 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -873,6 +873,17 @@ config OLD_SIGACTION
>  config COMPAT_OLD_SIGACTION
> >  	bool
>  
> +config ARCH_HAS_64BIT_TIME
> +	def_bool n
> +
> +config 64BIT_TIME
> +	def_bool ARCH_HAS_64BIT_TIME
> +	help
> +	  This should be selected by all architectures that need to support
> +	  new system calls with a 64-bit time_t. This is relevant on all 32-bit
> +	  architectures, and 64-bit architectures as part of compat syscall
> +	  handling.

Doesn't this text belong with ARCH_HAS_64BIT_TIME?

Ben.

> +
>  config ARCH_NO_COHERENT_DMA_MMAP
>  	bool
>  
-- 
Ben Hutchings
Software Developer, Codethink Ltd.