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> > - if (kstrtouint(buf, 10, &res) < 0 || res > MAX_PAGE_ORDER / 2) { > - pr_err("Bad debug_guardpage_minorder value: %s\n", buf); > + if (!buf || kstrtouint(buf, 10, &res) < 0 || res > MAX_PAGE_ORDER / 2) { > + pr_err("Bad debug_guardpage_minorder value: %s\n", buf ?: "(missing)"); > return 0; > } > _debug_guardpage_minorder = res; thanks, -- John Hubbard