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Thanks. > > Fixes: c0a32fc5a2e4 ("mm: more intensive memory corruption debugging") > Looks good, Reviewed-by: John Hubbard thanks, -- John Hubbard >> >>> Signed-off-by: Ye Liu >>> --- >>> mm/debug_page_alloc.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/mm/debug_page_alloc.c b/mm/debug_page_alloc.c >>> index 41e3d1f1ad96..fd2664c3c86a 100644 >>> --- a/mm/debug_page_alloc.c >>> +++ b/mm/debug_page_alloc.c >>> @@ -22,8 +22,8 @@ static int __init debug_guardpage_minorder_setup(char *buf) >>> { >>> unsigned int res; >>> >>> - 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, >