[LTP] [PATCH v2] syscalls: add syscall syncfs test

[Sumit Garg]

Hi Xiao,

On Fri, 15 Feb 2019 at 13:25, Xiao Yang <yangx.jy@cn.fujitsu.com> wrote:
>
> Hi Sumit,
>
> Sorry for the late reply. :-)
>
> 1) Compilation failed on older kernel(e.g. v2.6.32) because of the
> undefined syncfs().
> According to manpage, syncfs() was first appeared in Linux 2.6.39 and
> library
> support was added to glibc in version 2.14. Perhaps, we need to check if
> syncfs()
> is defined.
>
> 2) Running this test got TBROK on older kernel(e.g. v3.10.0), as below:
> -------------------------------------------------------------------
> syncfs01.c:63: FAIL: Failed to sync test filesystem to device
> -------------------------------------------------------------------
> It seems that the content of /sys/block/<loopX>/stat is always zero and
> doesn't update even though write and sync have been done. I am looking
> into it, but i am not sure if this is a known bug on older kernel.
>

Did you get a chance to root cause this issue?

I am not able to reproduce setup running kernel v3.10. If possible,
can you please share your setup details?

As Cyril suggested, we could solve this issue via configuring min_kver
value. But I am not sure regarding appropriate value.

BTW, as this seems to be kernel issue (/sys/block/<loopX>/stat not
updated), do we really don't want to run this test-case on old kernel
where it fails? To me this failure case is value add for user of old
kernel to be aware about this issue and probably fix it.

-Sumit

> Best Regards,
> Xiao Yang