From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 00/25] Change time_t and clock_t to 64 bit
Date: Fri, 16 May 2014 16:11:35 -0700
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References: <1399971456-3941-1-git-send-email-lftan@altera.com> <4706636.rTYoqSXXOR@wuerfel> <Pine.LNX.4.64.1405151949160.911@digraph.polyomino.org.uk> <9236147.lyD24Zv5SZ@wuerfel>
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To: Arnd Bergmann <arnd@arndb.de>, "Joseph S. Myers" <joseph@codesourcery.com>
Cc: Chung-Lin Tang <cltang@codesourcery.com>, John Stultz <john.stultz@linaro.org>, Geert Uytterhoeven <geert@linux-m68k.org>, Christoph Hellwig <hch@infradead.org>, Thomas Gleixner <tglx@linutronix.de>, Ley Foon Tan <lftan@altera.com>, Linux-Arch <linux-arch@vger.kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, LeyFoon Tan <lftan.linux@gmail.com>

On 05/15/2014 01:38 PM, Arnd Bergmann wrote:
> 
> For practical purposes in the kernel, we may still want to use 64-bit
> nanoseconds: if we use a 96 bit struct timespec, that would be incompatible
> with the native type on 64-bit kernels, thus complicating the syscall
> emulation layer.
> 
> I don't know why timespec on x32 uses 'long tv_nsec', it does seem
> problematic.

struct timespec is specified in POSIX as having type "long" for tv_nsec.
 This, as Linus pointed out, is totally braindamaged.

x32 does not follow POSIX (Linus pretty much dictated that), and instead
does the __kernel_suseconds_t to match the native kernel type.  The
proposal at some point was to try to push a snseconds_t into POSIX.

	-hpa