Re: 6.6.y: cifs broken since 6.6.23 writing big files with vers=1.0 and 2.0

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Jun 11, 2024 at 09:20:33AM +0200, Thomas Voegtle wrote:
> 
> Hello,
> 
> a machine booted with Linux 6.6.23 up to 6.6.32:
> 
> writing /dev/zero with dd on a mounted cifs share with vers=1.0 or
> vers=2.0 slows down drastically in my setup after writing approx. 46GB of
> data.
> 
> The whole machine gets unresponsive as it was under very high IO load. It
> pings but opening a new ssh session needs too much time. I can stop the dd
> (ctrl-c) and after a few minutes the machine is fine again.
> 
> cifs with vers=3.1.1 seems to be fine with 6.6.32.
> Linux 6.10-rc3 is fine with vers=1.0 and vers=2.0.
> 
> Bisected down to:
> 
> cifs-fix-writeback-data-corruption.patch
> which is:
> Upstream commit f3dc1bdb6b0b0693562c7c54a6c28bafa608ba3c
> and
> linux-stable commit e45deec35bf7f1f4f992a707b2d04a8c162f2240
> 
> Reverting this patch on 6.6.32 fixes the problem for me.

Odd, that commit is kind of needed :(

Is there some later commit that resolves the issue here that we should
pick up for the stable trees?

thanks,

greg k-h