On Mon, 01/03/2021 at 13.04 +0000, Damien Le Moal wrote: > Yes, I believe that: your patch disables the write cache ! So no > synchronize > cache command, no caching, no data loss. All good. [...] > Because the drive does not have synchronize cache while caching data, > which is > crazy. [...] > Sure, because you end up with WCE=0. All good. [...] > I understand the situation perfectly. I am not doubting your result. > I looked at > your patch and understand it. It is sensible, but does not plug all > the possible > holes with such weird drive. So that is not a good solution to me. It is the only possible solution to the best of my knowledge. > The alternative, safe this one, is a udev rule disabling your drive > write cache > or you setting the permanent drive config with WCE=0. That will have > *exactly* > the same effect as your patch: things will work just fine. Try that > solution > please. No need for a kernel patch. That is a cumbersome trick, not a safe and stable solution. The simplest point of failure of such trick is that an unexperienced user plugs in one of such drives without knowing the trick and data corruption occurs. Another very big disadvantage is that on multiple systems the same configuration needs to be replicated over and over on all systems. Guido
