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 for linux-mtd@lists.infradead.org; Mon, 02 Jul 2018 14:24:29 +0000
From: Richard Weinberger <richard@nod.at>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Artem Bityutskiy <dedekind1@gmail.com>,
 Adrian Hunter <adrian.hunter@intel.com>, y2038@lists.linaro.org,
 Deepa Dinamani <deepa.kernel@gmail.com>, linux-mtd@lists.infradead.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ubifs: tnc: use monotonic znode timestamp
Date: Mon, 02 Jul 2018 16:24:15 +0200
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Arnd,

Am Mittwoch, 20. Juni 2018, 10:29:11 CEST schrieb Arnd Bergmann:
> The tnc uses get_seconds() based timestamps to check the age of a znode,
> which has two problems: on 32-bit architectures this may overflow in
> 2038 or 2106, and it gives incorrect information when the system time
> is updated using settimeofday().
> 
> Using montonic timestamps with ktime_get_seconds() solves both thes
> problems.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  fs/ubifs/shrinker.c | 2 +-
>  fs/ubifs/tnc.c      | 4 ++--
>  fs/ubifs/tnc_misc.c | 2 +-
>  fs/ubifs/ubifs.h    | 2 +-
>  4 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/ubifs/shrinker.c b/fs/ubifs/shrinker.c
> index 9a9fb94a41c6..9d10cbdec2cc 100644
> --- a/fs/ubifs/shrinker.c
> +++ b/fs/ubifs/shrinker.c
> @@ -71,7 +71,7 @@ static int shrink_tnc(struct ubifs_info *c, int nr, int age, int *contention)
>  {
>  	int total_freed = 0;
>  	struct ubifs_znode *znode, *zprev;
> -	int time = get_seconds();
> +	time64_t time = ktime_get_seconds();

ubifs does
	abs(time - znode->time) >= age) {

Is this still legit with time64_t?

Thanks,
//richard