On Thu, 8 Apr 2021 14:39:09 +0000 "Luck, Tony" <tony.luck@xxxxxxxxx> wrote: > > I have one scenario, may you take into account: > > > > If one copyin case occurs, write() returned by your patch, the user process may > > check the return values, for errors, it may exit the process, then the error page > > will be freed, and then the page maybe alloced to other process or to kernel itself, > > then code will initialize it and this will trigger one SRAO, if it's used by kernel, > > we may do nothing for this, and kernel may still touch it, and lead to one panic. > > In this case kill_me_never() calls memory_failure() with flags == 0. I think (hope!) > that means that it will unmap the page from the task, but will not send a signal. > > When the task exits the PTE for this page has the swap/poison signature, so the > page is not freed for re-use. > > -Tony Oh, Yes, Sorry for my rudeness and error-understandings, I just happen to can't control my emotions and get confused for some other things. Thanks! Aili Yao
