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But this also fixed a real bug >>>> too. So, it's not appropriate just to revert it blindly. >>> >>> Linus was clear about this recently. Even if it fixes a bug, regression is >>> still regression and might (*) lead to a revert. >>> https://lwn.net/Articles/990599/ >>> >>> (*) in general fixes are better than reverts, but depends on the timing in >>> the release cycle the revert may be the only option. >> >> I don't think that the timing is so tight that we should not work on >> proper fix firstly. I'm trying to work with the reporter on this. > > I agree on this, please do. > >> BTW, the commit b4afe4183ec7 ("resource: fix region_intersects() vs >> add_memory_driver_managed()") fixed a security related bug. The bug >> weakened the protection to prevent users read/write system memory via >> /dev/mem. So, IMO, we need to be more careful about this. > > My point was that the regression is obvious and it needs to be fixed. > That's all. Revert is a last resort in this sense. > I agree in general to both of your comment. (i.e. since this bisected commit had security fix, we shall try to get better fix than a close to revert). I am trying to work on this, but it is a bit slow on my side. Thanks and Regards - Raghu