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>> + >> +        /* >> +         * The __get_user_pages_locked() call happens before we know >> +         * that whether it's possible to successfully complete the whole oops, s/that whether/that/ >> +         * operation. To compensate for this, if we get an unexpected >> +         * error (such as -ENOMEM) then we must unpin everything, before >> +         * erroring out. >> +         */ >> +        if (rc != -EAGAIN && rc != 0) >> +            unpin_user_pages(pages, nr_pinned_pages); >> + >>       } while (rc == -EAGAIN); > > Wouldn't it be cleaner to simply have here after the loop (possibly even > after the memalloc_pin_restore()) > > if (rc) >     unpin_user_pages(pages, nr_pinned_pages); > > But maybe I am missing something. Yes, I think you are correct. That is cleaner. Let me retest real quick just in case, and then send a v2 that also picks up the typo and moves the comment to the new location. thanks, -- John Hubbard