Re: [PATCH 1/2] fs: initialize inode->__i_ctime to the epoch

From: Jan Kara
Date: Fri Sep 08 2023 - 06:42:37 EST


On Thu 07-09-23 12:33:47, Jeff Layton wrote:
> With the advent of multigrain timestamps, we use inode_set_ctime_current
> to set the ctime, which can skip updating if the existing ctime appears
> to be in the future. Because we don't initialize this field at
> allocation time, that could prevent the ctime from being initialized
> properly when the inode is instantiated.
>
> Always initialize the ctime field to the epoch so that the filesystem
> can set the timestamps properly later.
>
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-lkp/202309071017.a64aca5e-oliver.sang@xxxxxxxxx
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>

Looks good but don't you need the same treatment to atime after your patch
2/2?

Honza

> ---
> fs/inode.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/fs/inode.c b/fs/inode.c
> index 35fd688168c5..54237f4242ff 100644
> --- a/fs/inode.c
> +++ b/fs/inode.c
> @@ -168,6 +168,8 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
> inode->i_fop = &no_open_fops;
> inode->i_ino = 0;
> inode->__i_nlink = 1;
> + inode->__i_ctime.tv_sec = 0;
> + inode->__i_ctime.tv_nsec = 0;
> inode->i_opflags = 0;
> if (sb->s_xattr)
> inode->i_opflags |= IOP_XATTR;
>
> --
> 2.41.0
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR