| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <202505152339.fBOfDPsi-lkp@intel.com>
Date: Fri, 23 May 2025 13:47:54 +0300
From: Dan Carpenter <dan.carpenter@...aro.org>
To: oe-kbuild@...ts.linux.dev, Yu Zhao <yuzhao@...gle.com>
Cc: lkp@...el.com, oe-kbuild-all@...ts.linux.dev,
linux-kernel@...r.kernel.org,
Andrew Morton <akpm@...ux-foundation.org>,
Linux Memory Management List <linux-mm@...ck.org>
Subject: mm/vmscan.c:3504 walk_pte_range() error: uninitialized symbol
'dirty'.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 088d13246a4672bc03aec664675138e3f5bff68c
commit: a52dcec56c5b96250f15efbd7de3d3ea6ce863d9 mm/mglru: fix PTE-mapped large folios
config: sparc-randconfig-r073-20250515 (https://download.01.org/0day-ci/archive/20250515/202505152339.fBOfDPsi-lkp@intel.com/config)
compiler: sparc64-linux-gcc (GCC) 8.5.0
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@...el.com>
| Reported-by: Dan Carpenter <dan.carpenter@...aro.org>
| Closes: https://lore.kernel.org/r/202505152339.fBOfDPsi-lkp@intel.com/
smatch warnings:
mm/vmscan.c:3504 walk_pte_range() error: uninitialized symbol 'dirty'.
mm/vmscan.c:3595 walk_pmd_range_locked() error: uninitialized symbol 'dirty'.
mm/vmscan.c:4215 lru_gen_look_around() error: uninitialized symbol 'dirty'.
vim +/dirty +3504 mm/vmscan.c
bd74fdaea14602 Yu Zhao 2022-09-18 3450 static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end,
bd74fdaea14602 Yu Zhao 2022-09-18 3451 struct mm_walk *args)
bd74fdaea14602 Yu Zhao 2022-09-18 3452 {
bd74fdaea14602 Yu Zhao 2022-09-18 3453 int i;
a52dcec56c5b96 Yu Zhao 2024-12-30 3454 bool dirty;
bd74fdaea14602 Yu Zhao 2022-09-18 3455 pte_t *pte;
bd74fdaea14602 Yu Zhao 2022-09-18 3456 spinlock_t *ptl;
bd74fdaea14602 Yu Zhao 2022-09-18 3457 unsigned long addr;
bd74fdaea14602 Yu Zhao 2022-09-18 3458 int total = 0;
bd74fdaea14602 Yu Zhao 2022-09-18 3459 int young = 0;
a52dcec56c5b96 Yu Zhao 2024-12-30 3460 struct folio *last = NULL;
bd74fdaea14602 Yu Zhao 2022-09-18 3461 struct lru_gen_mm_walk *walk = args->private;
bd74fdaea14602 Yu Zhao 2022-09-18 3462 struct mem_cgroup *memcg = lruvec_memcg(walk->lruvec);
bd74fdaea14602 Yu Zhao 2022-09-18 3463 struct pglist_data *pgdat = lruvec_pgdat(walk->lruvec);
cc25bbe10a86a7 Kinsey Ho 2024-02-14 3464 DEFINE_MAX_SEQ(walk->lruvec);
a52dcec56c5b96 Yu Zhao 2024-12-30 3465 int gen = lru_gen_from_seq(max_seq);
2441774f2d2890 Qi Zheng 2024-09-26 3466 pmd_t pmdval;
bd74fdaea14602 Yu Zhao 2022-09-18 3467
a52dcec56c5b96 Yu Zhao 2024-12-30 3468 pte = pte_offset_map_rw_nolock(args->mm, pmd, start & PMD_MASK, &pmdval, &ptl);
52fc048320adf1 Hugh Dickins 2023-06-08 3469 if (!pte)
52fc048320adf1 Hugh Dickins 2023-06-08 3470 return false;
a52dcec56c5b96 Yu Zhao 2024-12-30 3471
52fc048320adf1 Hugh Dickins 2023-06-08 3472 if (!spin_trylock(ptl)) {
52fc048320adf1 Hugh Dickins 2023-06-08 3473 pte_unmap(pte);
a52dcec56c5b96 Yu Zhao 2024-12-30 3474 return true;
52fc048320adf1 Hugh Dickins 2023-06-08 3475 }
bd74fdaea14602 Yu Zhao 2022-09-18 3476
2441774f2d2890 Qi Zheng 2024-09-26 3477 if (unlikely(!pmd_same(pmdval, pmdp_get_lockless(pmd)))) {
2441774f2d2890 Qi Zheng 2024-09-26 3478 pte_unmap_unlock(pte, ptl);
2441774f2d2890 Qi Zheng 2024-09-26 3479 return false;
2441774f2d2890 Qi Zheng 2024-09-26 3480 }
2441774f2d2890 Qi Zheng 2024-09-26 3481
bd74fdaea14602 Yu Zhao 2022-09-18 3482 arch_enter_lazy_mmu_mode();
bd74fdaea14602 Yu Zhao 2022-09-18 3483 restart:
bd74fdaea14602 Yu Zhao 2022-09-18 3484 for (i = pte_index(start), addr = start; addr != end; i++, addr += PAGE_SIZE) {
bd74fdaea14602 Yu Zhao 2022-09-18 3485 unsigned long pfn;
bd74fdaea14602 Yu Zhao 2022-09-18 3486 struct folio *folio;
c33c794828f212 Ryan Roberts 2023-06-12 3487 pte_t ptent = ptep_get(pte + i);
bd74fdaea14602 Yu Zhao 2022-09-18 3488
bd74fdaea14602 Yu Zhao 2022-09-18 3489 total++;
bd74fdaea14602 Yu Zhao 2022-09-18 3490 walk->mm_stats[MM_LEAF_TOTAL]++;
bd74fdaea14602 Yu Zhao 2022-09-18 3491
1d4832becdc2cd Yu Zhao 2024-10-19 3492 pfn = get_pte_pfn(ptent, args->vma, addr, pgdat);
bd74fdaea14602 Yu Zhao 2022-09-18 3493 if (pfn == -1)
bd74fdaea14602 Yu Zhao 2022-09-18 3494 continue;
bd74fdaea14602 Yu Zhao 2022-09-18 3495
798c0330c2ca07 Yu Zhao 2024-12-30 3496 folio = get_pfn_folio(pfn, memcg, pgdat);
bd74fdaea14602 Yu Zhao 2022-09-18 3497 if (!folio)
bd74fdaea14602 Yu Zhao 2022-09-18 3498 continue;
bd74fdaea14602 Yu Zhao 2022-09-18 3499
1d4832becdc2cd Yu Zhao 2024-10-19 3500 if (!ptep_clear_young_notify(args->vma, addr, pte + i))
1d4832becdc2cd Yu Zhao 2024-10-19 3501 continue;
bd74fdaea14602 Yu Zhao 2022-09-18 3502
a52dcec56c5b96 Yu Zhao 2024-12-30 3503 if (last != folio) {
a52dcec56c5b96 Yu Zhao 2024-12-30 @3504 walk_update_folio(walk, last, gen, dirty);
^^^^^
Potentially uninitialized.
It's weird that I didn't report this in Jan because it seems like a
reasonable warning. Sorry for that.
bd74fdaea14602 Yu Zhao 2022-09-18 3505
a52dcec56c5b96 Yu Zhao 2024-12-30 3506 last = folio;
a52dcec56c5b96 Yu Zhao 2024-12-30 3507 dirty = false;
a52dcec56c5b96 Yu Zhao 2024-12-30 3508 }
bd74fdaea14602 Yu Zhao 2022-09-18 3509
a52dcec56c5b96 Yu Zhao 2024-12-30 3510 if (pte_dirty(ptent))
a52dcec56c5b96 Yu Zhao 2024-12-30 3511 dirty = true;
a52dcec56c5b96 Yu Zhao 2024-12-30 3512
a52dcec56c5b96 Yu Zhao 2024-12-30 3513 young++;
a52dcec56c5b96 Yu Zhao 2024-12-30 3514 walk->mm_stats[MM_LEAF_YOUNG]++;
bd74fdaea14602 Yu Zhao 2022-09-18 3515 }
bd74fdaea14602 Yu Zhao 2022-09-18 3516
a52dcec56c5b96 Yu Zhao 2024-12-30 3517 walk_update_folio(walk, last, gen, dirty);
a52dcec56c5b96 Yu Zhao 2024-12-30 3518 last = NULL;
a52dcec56c5b96 Yu Zhao 2024-12-30 3519
bd74fdaea14602 Yu Zhao 2022-09-18 3520 if (i < PTRS_PER_PTE && get_next_vma(PMD_MASK, PAGE_SIZE, args, &start, &end))
bd74fdaea14602 Yu Zhao 2022-09-18 3521 goto restart;
bd74fdaea14602 Yu Zhao 2022-09-18 3522
bd74fdaea14602 Yu Zhao 2022-09-18 3523 arch_leave_lazy_mmu_mode();
52fc048320adf1 Hugh Dickins 2023-06-08 3524 pte_unmap_unlock(pte, ptl);
bd74fdaea14602 Yu Zhao 2022-09-18 3525
bd74fdaea14602 Yu Zhao 2022-09-18 3526 return suitable_to_scan(total, young);
bd74fdaea14602 Yu Zhao 2022-09-18 3527 }
bd74fdaea14602 Yu Zhao 2022-09-18 3528
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3529 static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area_struct *vma,
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3530 struct mm_walk *args, unsigned long *bitmap, unsigned long *first)
bd74fdaea14602 Yu Zhao 2022-09-18 3531 {
bd74fdaea14602 Yu Zhao 2022-09-18 3532 int i;
a52dcec56c5b96 Yu Zhao 2024-12-30 3533 bool dirty;
bd74fdaea14602 Yu Zhao 2022-09-18 3534 pmd_t *pmd;
bd74fdaea14602 Yu Zhao 2022-09-18 3535 spinlock_t *ptl;
a52dcec56c5b96 Yu Zhao 2024-12-30 3536 struct folio *last = NULL;
bd74fdaea14602 Yu Zhao 2022-09-18 3537 struct lru_gen_mm_walk *walk = args->private;
bd74fdaea14602 Yu Zhao 2022-09-18 3538 struct mem_cgroup *memcg = lruvec_memcg(walk->lruvec);
bd74fdaea14602 Yu Zhao 2022-09-18 3539 struct pglist_data *pgdat = lruvec_pgdat(walk->lruvec);
cc25bbe10a86a7 Kinsey Ho 2024-02-14 3540 DEFINE_MAX_SEQ(walk->lruvec);
a52dcec56c5b96 Yu Zhao 2024-12-30 3541 int gen = lru_gen_from_seq(max_seq);
bd74fdaea14602 Yu Zhao 2022-09-18 3542
bd74fdaea14602 Yu Zhao 2022-09-18 3543 VM_WARN_ON_ONCE(pud_leaf(*pud));
bd74fdaea14602 Yu Zhao 2022-09-18 3544
bd74fdaea14602 Yu Zhao 2022-09-18 3545 /* try to batch at most 1+MIN_LRU_BATCH+1 entries */
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3546 if (*first == -1) {
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3547 *first = addr;
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3548 bitmap_zero(bitmap, MIN_LRU_BATCH);
bd74fdaea14602 Yu Zhao 2022-09-18 3549 return;
bd74fdaea14602 Yu Zhao 2022-09-18 3550 }
bd74fdaea14602 Yu Zhao 2022-09-18 3551
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3552 i = addr == -1 ? 0 : pmd_index(addr) - pmd_index(*first);
bd74fdaea14602 Yu Zhao 2022-09-18 3553 if (i && i <= MIN_LRU_BATCH) {
bd74fdaea14602 Yu Zhao 2022-09-18 3554 __set_bit(i - 1, bitmap);
bd74fdaea14602 Yu Zhao 2022-09-18 3555 return;
bd74fdaea14602 Yu Zhao 2022-09-18 3556 }
bd74fdaea14602 Yu Zhao 2022-09-18 3557
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3558 pmd = pmd_offset(pud, *first);
bd74fdaea14602 Yu Zhao 2022-09-18 3559
bd74fdaea14602 Yu Zhao 2022-09-18 3560 ptl = pmd_lockptr(args->mm, pmd);
bd74fdaea14602 Yu Zhao 2022-09-18 3561 if (!spin_trylock(ptl))
bd74fdaea14602 Yu Zhao 2022-09-18 3562 goto done;
bd74fdaea14602 Yu Zhao 2022-09-18 3563
bd74fdaea14602 Yu Zhao 2022-09-18 3564 arch_enter_lazy_mmu_mode();
bd74fdaea14602 Yu Zhao 2022-09-18 3565
bd74fdaea14602 Yu Zhao 2022-09-18 3566 do {
bd74fdaea14602 Yu Zhao 2022-09-18 3567 unsigned long pfn;
bd74fdaea14602 Yu Zhao 2022-09-18 3568 struct folio *folio;
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3569
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3570 /* don't round down the first address */
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3571 addr = i ? (*first & PMD_MASK) + i * PMD_SIZE : *first;
bd74fdaea14602 Yu Zhao 2022-09-18 3572
1d4832becdc2cd Yu Zhao 2024-10-19 3573 if (!pmd_present(pmd[i]))
bd74fdaea14602 Yu Zhao 2022-09-18 3574 goto next;
bd74fdaea14602 Yu Zhao 2022-09-18 3575
bd74fdaea14602 Yu Zhao 2022-09-18 3576 if (!pmd_trans_huge(pmd[i])) {
1d4832becdc2cd Yu Zhao 2024-10-19 3577 if (!walk->force_scan && should_clear_pmd_young() &&
1d4832becdc2cd Yu Zhao 2024-10-19 3578 !mm_has_notifiers(args->mm))
bd74fdaea14602 Yu Zhao 2022-09-18 3579 pmdp_test_and_clear_young(vma, addr, pmd + i);
bd74fdaea14602 Yu Zhao 2022-09-18 3580 goto next;
bd74fdaea14602 Yu Zhao 2022-09-18 3581 }
bd74fdaea14602 Yu Zhao 2022-09-18 3582
1d4832becdc2cd Yu Zhao 2024-10-19 3583 pfn = get_pmd_pfn(pmd[i], vma, addr, pgdat);
1d4832becdc2cd Yu Zhao 2024-10-19 3584 if (pfn == -1)
1d4832becdc2cd Yu Zhao 2024-10-19 3585 goto next;
1d4832becdc2cd Yu Zhao 2024-10-19 3586
798c0330c2ca07 Yu Zhao 2024-12-30 3587 folio = get_pfn_folio(pfn, memcg, pgdat);
bd74fdaea14602 Yu Zhao 2022-09-18 3588 if (!folio)
bd74fdaea14602 Yu Zhao 2022-09-18 3589 goto next;
bd74fdaea14602 Yu Zhao 2022-09-18 3590
1d4832becdc2cd Yu Zhao 2024-10-19 3591 if (!pmdp_clear_young_notify(vma, addr, pmd + i))
bd74fdaea14602 Yu Zhao 2022-09-18 3592 goto next;
bd74fdaea14602 Yu Zhao 2022-09-18 3593
a52dcec56c5b96 Yu Zhao 2024-12-30 3594 if (last != folio) {
a52dcec56c5b96 Yu Zhao 2024-12-30 @3595 walk_update_folio(walk, last, gen, dirty);
Same.
bd74fdaea14602 Yu Zhao 2022-09-18 3596
a52dcec56c5b96 Yu Zhao 2024-12-30 3597 last = folio;
a52dcec56c5b96 Yu Zhao 2024-12-30 3598 dirty = false;
a52dcec56c5b96 Yu Zhao 2024-12-30 3599 }
bd74fdaea14602 Yu Zhao 2022-09-18 3600
a52dcec56c5b96 Yu Zhao 2024-12-30 3601 if (pmd_dirty(pmd[i]))
a52dcec56c5b96 Yu Zhao 2024-12-30 3602 dirty = true;
a52dcec56c5b96 Yu Zhao 2024-12-30 3603
a52dcec56c5b96 Yu Zhao 2024-12-30 3604 walk->mm_stats[MM_LEAF_YOUNG]++;
bd74fdaea14602 Yu Zhao 2022-09-18 3605 next:
bd74fdaea14602 Yu Zhao 2022-09-18 3606 i = i > MIN_LRU_BATCH ? 0 : find_next_bit(bitmap, MIN_LRU_BATCH, i) + 1;
bd74fdaea14602 Yu Zhao 2022-09-18 3607 } while (i <= MIN_LRU_BATCH);
bd74fdaea14602 Yu Zhao 2022-09-18 3608
a52dcec56c5b96 Yu Zhao 2024-12-30 3609 walk_update_folio(walk, last, gen, dirty);
a52dcec56c5b96 Yu Zhao 2024-12-30 3610
bd74fdaea14602 Yu Zhao 2022-09-18 3611 arch_leave_lazy_mmu_mode();
bd74fdaea14602 Yu Zhao 2022-09-18 3612 spin_unlock(ptl);
bd74fdaea14602 Yu Zhao 2022-09-18 3613 done:
b5ff4133617d0e T.J. Alumbaugh 2023-01-18 3614 *first = -1;
bd74fdaea14602 Yu Zhao 2022-09-18 3615 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Powered by blists - more mailing lists