[PATCH] erofs: derive atime instead of leaving it empty

[Gao Xiang]

Hi Chao,

On Sun, Nov 01, 2020 at 03:51:02AM +0800, Gao Xiang wrote:
> From: Gao Xiang <hsiangkao at redhat.com>
> 
> EROFS has _only one_ ondisk timestamp (ctime is currently
> documented and recorded, we might also record mtime instead
> with a new compat feature if needed) for each extended inode
> since EROFS isn't mainly for archival purposes so no need to
> keep all timestamps on disk especially for Android scenarios
> due to security concerns. Also, romfs/cramfs don't have their
> own on-disk timestamp, and squashfs only records mtime instead.
> 
> Let's also derive access time from ondisk timestamp rather than
> leaving it empty, and if mtime/atime for each file are really
> needed for specific scenarios as well, we can also use xattrs
> to record them then.
> 
> Reported-by: nl6720 <nl6720 at gmail.com>
> [ Gao Xiang: It'd be better to backport for user-friendly concern. ]
> Fixes: 431339ba9042 ("staging: erofs: add inode operations")
> Cc: stable <stable at vger.kernel.org> # 4.19+
> Signed-off-by: Gao Xiang <hsiangkao at redhat.com>

May I ask for some extra free slots to review this patch plus 
[PATCH 1/4] of 
https://lore.kernel.org/r/20201022145724.27284-1-hsiangkao@aol.com

since it'd be also in linux-next for a while before sending out
to Linus. And the debugging messages may also be an annoying
thing for users.

Thanks a lot!

Thanks,
Gao Xiang