Race between sync(2) and inode wb switching

[Liu Bo <obuil.liubo@xxxxxxxxx>]

Hi Tejun,

Seems that the following patch[1] never got landed in kernel, can you
please queue it again?

[1]: https://lore.kernel.org/patchwork/patch/862149/
writeback: synchronize sync(2) against cgroup writeback membership switches

thanks,
liubo