Hi Michał, kernel test robot noticed the following build errors: [auto build test ERROR on akpm-mm/mm-everything] [also build test ERROR on linus/master v6.5-rc2 next-20230721] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Micha-Miros-aw/fs-proc-task_mmu-Implement-IOCTL-for-efficient-page-table-scanning/20230722-082500 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/ZLshsAj5PbsEAHhP%40qmqm.qmqm.pl patch subject: [v2] fs/proc/task_mmu: Implement IOCTL for efficient page table scanning config: x86_64-rhel-8.3-rust (https://download.01.org/0day-ci/archive/20230722/202307222107.GdtIG4nq-lkp@xxxxxxxxx/config) compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a) reproduce: (https://download.01.org/0day-ci/archive/20230722/202307222107.GdtIG4nq-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202307222107.GdtIG4nq-lkp@xxxxxxxxx/ All errors (new ones prefixed by >>): fs/proc/task_mmu.c:1921:6: error: call to undeclared function 'userfaultfd_wp_async'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration] if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) ^ >> fs/proc/task_mmu.c:2047:13: error: use of undeclared identifier 'addr' if (end != addr + HPAGE_SIZE) { ^ 2 errors generated. vim +/addr +2047 fs/proc/task_mmu.c 1913 1914 static int pagemap_scan_test_walk(unsigned long start, unsigned long end, 1915 struct mm_walk *walk) 1916 { 1917 struct pagemap_scan_private *p = walk->private; 1918 struct vm_area_struct *vma = walk->vma; 1919 unsigned long vma_category = 0; 1920 > 1921 if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) 1922 vma_category |= PAGE_IS_WPASYNC; 1923 else if (p->arg.flags & PM_SCAN_CHECK_WPASYNC) 1924 return -EPERM; 1925 1926 if (vma->vm_flags & VM_PFNMAP) 1927 return 1; 1928 1929 if (!pagemap_scan_is_interesting_vma(vma_category, p)) 1930 return 1; 1931 1932 p->cur_vma_category = vma_category; 1933 return 0; 1934 } 1935 1936 static bool pagemap_scan_push_range(unsigned long categories, 1937 struct pagemap_scan_private *p, 1938 unsigned long addr, unsigned long end) 1939 { 1940 struct page_region *cur_buf = &p->cur_buf; 1941 1942 /* 1943 * When there is no output buffer provided at all, the sentinel values 1944 * won't match here. There is no other way for `cur_buf->end` to be 1945 * non-zero other than it being non-empty. 1946 */ 1947 if (addr == cur_buf->end && categories == cur_buf->categories) { 1948 cur_buf->end = end; 1949 return true; 1950 } 1951 1952 if (cur_buf->end) { 1953 if (p->vec_buf_index >= p->vec_buf_len) 1954 return false; 1955 1956 memcpy(&p->vec_buf[p->vec_buf_index], cur_buf, 1957 sizeof(*p->vec_buf)); 1958 ++p->vec_buf_index; 1959 } 1960 1961 cur_buf->start = addr; 1962 cur_buf->end = end; 1963 cur_buf->categories = categories; 1964 return true; 1965 } 1966 1967 static void pagemap_scan_backout_range(struct pagemap_scan_private *p, 1968 unsigned long addr, unsigned long end) 1969 { 1970 struct page_region *cur_buf = &p->cur_buf; 1971 1972 if (cur_buf->start != addr) 1973 cur_buf->end = addr; 1974 else 1975 cur_buf->start = cur_buf->end = 0; 1976 1977 p->end_addr = 0; 1978 p->found_pages -= (end - addr) / PAGE_SIZE; 1979 } 1980 1981 static int pagemap_scan_output(unsigned long categories, 1982 struct pagemap_scan_private *p, 1983 unsigned long addr, unsigned long *end) 1984 { 1985 unsigned long n_pages, total_pages; 1986 int ret = 0; 1987 1988 if (!pagemap_scan_is_interesting_page(categories, p)) { 1989 *end = addr; 1990 return 0; 1991 } 1992 1993 if (!p->vec_buf) 1994 return 0; 1995 1996 categories &= p->arg.return_mask; 1997 1998 n_pages = (*end - addr) / PAGE_SIZE; 1999 if (check_add_overflow(p->found_pages, n_pages, &total_pages) || total_pages > p->arg.max_pages) { 2000 size_t n_too_much = total_pages - p->arg.max_pages; 2001 *end -= n_too_much * PAGE_SIZE; 2002 n_pages -= n_too_much; 2003 ret = -ENOSPC; 2004 } 2005 2006 if (!pagemap_scan_push_range(categories, p, addr, *end)) { 2007 *end = addr; 2008 n_pages = 0; 2009 ret = -ENOSPC; 2010 } 2011 2012 p->found_pages += n_pages; 2013 if (ret) 2014 p->end_addr = *end; 2015 return ret; 2016 } 2017 2018 static int pagemap_scan_thp_entry(pmd_t *pmd, unsigned long start, 2019 unsigned long end, struct mm_walk *walk) 2020 { 2021 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 2022 struct pagemap_scan_private *p = walk->private; 2023 struct vm_area_struct *vma = walk->vma; 2024 unsigned long categories; 2025 spinlock_t *ptl; 2026 int ret = 0; 2027 2028 ptl = pmd_trans_huge_lock(pmd, vma); 2029 if (!ptl) 2030 return -ENOENT; 2031 2032 categories = p->cur_vma_category | pagemap_thp_category(*pmd); 2033 2034 ret = pagemap_scan_output(categories, p, start, &end); 2035 if (start == end) 2036 goto out_unlock; 2037 2038 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2039 goto out_unlock; 2040 if (~categories & PAGE_IS_WRITTEN) 2041 goto out_unlock; 2042 2043 /* 2044 * Break huge page into small pages if the WP operation 2045 * need to be performed is on a portion of the huge page. 2046 */ > 2047 if (end != addr + HPAGE_SIZE) { 2048 spin_unlock(ptl); 2049 split_huge_pmd(vma, pmd, start); 2050 pagemap_scan_backout_range(p, start, end); 2051 return -ENOENT; 2052 } 2053 2054 make_uffd_wp_pmd(vma, start, pmd); 2055 flush_tlb_range(vma, start, end); 2056 out_unlock: 2057 spin_unlock(ptl); 2058 return ret; 2059 #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ 2060 return -ENOENT; 2061 #endif 2062 } 2063 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki