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>>> + char *orig; >>> + char *token; >>> + int ret; >>> + size_t max_input_len; >> >> This can be const size_t max_input_len = 32 with the comment above it. > > I don't think that local adds any value, really. How about > > --- a/mm/page_owner.c~mm-page_owner-add-print_mode-filter-fix > +++ a/mm/page_owner.c > @@ -933,7 +933,6 @@ static ssize_t page_owner_write(struct f > char *orig; > char *token; > int ret; > - size_t max_input_len; > struct page_owner_filter_state *state = file->private_data; > enum page_owner_print_mode new_print_mode; > unsigned long flags; > @@ -942,9 +941,7 @@ static ssize_t page_owner_write(struct f > * Maximum input length for filter commands: > * 32: print_mode command max length is 17 ("mode=stack_handle"). > */ > - max_input_len = 32; > - > - if (count > max_input_len) > + if (count > 32) > return -EINVAL; > > kbuf = memdup_user_nul(buf, count); > _ Looks good to me. Best Regards, Yan, Zi