linux-ext4 - Re: [PATCH 2/6] ext4: use 64-bit timestamps for mmp

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Date:   Fri, 22 Jun 2018 09:38:21 +0200
From:   Jan Kara <jack@...e.cz>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Theodore Ts'o <tytso@....edu>,
        Andreas Dilger <adilger.kernel@...ger.ca>,
        Jan Kara <jack@...e.com>, y2038@...ts.linaro.org,
        linux-ext4@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/6] ext4: use 64-bit timestamps for mmp_time

On Wed 20-06-18 17:32:59, Arnd Bergmann wrote:
> The mmp_time field is 64 bits wide, which is good, but calling
> get_seconds() results in a 32-bit value on 32-bit architectures. Using
> ktime_get_real_seconds() instead returns 64 bits everywhere.
> 
> Signed-off-by: Arnd Bergmann <arnd@...db.de>

Looks good.

Reviewed-by: Jan Kara <jack@...e.cz>

								Honza

> ---
>  fs/ext4/mmp.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c
> index 27b9a76a0dfa..39da4eb48361 100644
> --- a/fs/ext4/mmp.c
> +++ b/fs/ext4/mmp.c
> @@ -147,7 +147,7 @@ static int kmmpd(void *data)
>  
>  	mmp_block = le64_to_cpu(es->s_mmp_block);
>  	mmp = (struct mmp_struct *)(bh->b_data);
> -	mmp->mmp_time = cpu_to_le64(get_seconds());
> +	mmp->mmp_time = cpu_to_le64(ktime_get_real_seconds());
>  	/*
>  	 * Start with the higher mmp_check_interval and reduce it if
>  	 * the MMP block is being updated on time.
> @@ -165,7 +165,7 @@ static int kmmpd(void *data)
>  			seq = 1;
>  
>  		mmp->mmp_seq = cpu_to_le32(seq);
> -		mmp->mmp_time = cpu_to_le64(get_seconds());
> +		mmp->mmp_time = cpu_to_le64(ktime_get_real_seconds());
>  		last_update_time = jiffies;
>  
>  		retval = write_mmp_block(sb, bh);
> @@ -244,7 +244,7 @@ static int kmmpd(void *data)
>  	 * Unmount seems to be clean.
>  	 */
>  	mmp->mmp_seq = cpu_to_le32(EXT4_MMP_SEQ_CLEAN);
> -	mmp->mmp_time = cpu_to_le64(get_seconds());
> +	mmp->mmp_time = cpu_to_le64(ktime_get_real_seconds());
>  
>  	retval = write_mmp_block(sb, bh);
>  
> -- 
> 2.9.0
> 
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR