On Tue, 7 Oct 2025 11:19:34 -0700 Runping Lai <[email protected]> wrote:
> Hey Steve, > > On Pixel6, CONFIG_PREEMPT is set. And CONFIG_PREEMPT_NONE > is not set. I'll paste the full PREEMPT configs: Hmm, now I'm curious to why _nofault() does't work but inatomic does. > > > > > The original code is buggy, but if this is causing a regression, then we > > likely need to do something else, like copy in a pre-allocated buffer? > > Sounds like a good plan. Before the long term fix, can we please > revert this commit? Not that easy as the old way has a legitimate bug in it. Could you see if adding pagefault_disable() and pagefault_enable() around the __copy_from_user_inatomic() works for you? Or does that have the same problem? I do have a working solution, but it isn't trivial. -- Steve
