bug#41495: stat birth time issues with coreutils-8.32

[Andrew Mahoney]

On 2020-05-24 7:45 a.m., Pádraig Brady wrote:
> On 23/05/2020 22:58, Andy wrote:
> > On my arch linux system, I can't see birth time with coreutils-8.32 with
> > either of
> > - zfs mounts
> > - ext4 mounts
> >
> > But I am having success with:
> > - smb mounts
> >
> > ==============
> > System details:
> >
> > stat --version
> >   > stat (GNU coreutils) 8.32
> >
> > pacman -Qi coreutils
> >   > version 8.32-1
> >
> > uname -a
> >   > 5.6.14-arch1-1 #1 SMP PREEMPT Wed, 20 May 2020 20:43:19 +0000 x86_64
> > GNU/Linux
> >
> >
> > ==========================
> > Reproducible example with ext4 mount:
> >
> > dd if=/dev/zero of=test.img bs=1M count=10
> > mkfs.ext4 test.img
> > mkdir testext4
> > sudo mount -o loop test.img ~/testext4
> > sudo chown -R andy:andy testext4
> > touch testext4/bloop
> > stat testext4/bloop
> >
> >     File: testext4/bloop
> >     Size: 0               Blocks: 0          IO Block: 1024 regular 
> > empty
> > file
> > Device: 700h/1792d      Inode: 12          Links: 1
> > Access: (0644/-rw-r--r--)  Uid: ( 1000/    andy)   Gid: ( 1000/ andy)
> > Access: 2020-05-23 13:48:01.000000000 -0700
> > Modify: 2020-05-23 13:47:59.000000000 -0700
> > Change: 2020-05-23 13:47:59.000000000 -0700
> >    Birth: -
>
> I think your ext4 file system may be too small to have appropriately
> sized indoes to support birth time. The man page suggests you
> would have 128 byte inodes for such a small file system.
> You should be able to override that with: mkfs.ext4 -I 256 test.img

Thanks you are correct, birth time appears correctly with that option.

I think this can be closed, not a bug with coreutils. For the remaining 
issue it seems zfs doesn't support statx with birth time yet:

https://github.com/openzfs/zfs/issues/8507