The patch titled
Subject: mm-swapfile-fix-possible-data-races-of-inuse_pages-v3
has been added to the -mm mm-unstable branch. Its filename is
mm-swapfile-fix-possible-data-races-of-inuse_pages-v3.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swapfile-fix-possible-data-races-of-inuse_pages-v3.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm-swapfile-fix-possible-data-races-of-inuse_pages-v3
Date: Sat, 25 Jun 2022 17:33:45 +0800
use WRITE_ONCE to pair with READ_ONCE
Link: https://lkml.kernel.org/r/20220625093346.48894-2-linmiaohe@xxxxxxxxxx
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swapfile.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/mm/swapfile.c~mm-swapfile-fix-possible-data-races-of-inuse_pages-v3
+++ a/mm/swapfile.c
@@ -695,7 +695,7 @@ static void swap_range_alloc(struct swap
si->lowest_bit += nr_entries;
if (end == si->highest_bit)
WRITE_ONCE(si->highest_bit, si->highest_bit - nr_entries);
- si->inuse_pages += nr_entries;
+ WRITE_ONCE(si->inuse_pages, si->inuse_pages + nr_entries);
if (si->inuse_pages == si->pages) {
si->lowest_bit = si->max;
si->highest_bit = 0;
@@ -732,7 +732,7 @@ static void swap_range_free(struct swap_
add_to_avail_list(si);
}
atomic_long_add(nr_entries, &nr_swap_pages);
- si->inuse_pages -= nr_entries;
+ WRITE_ONCE(si->inuse_pages, si->inuse_pages - nr_entries);
if (si->flags & SWP_BLKDEV)
swap_slot_free_notify =
si->bdev->bd_disk->fops->swap_slot_free_notify;
_
Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are
mm-migration-remove-unneeded-lock-page-and-pagemovable-check.patch
mm-migration-return-errno-when-isolate_huge_page-failed.patch
mm-migration-fix-potential-pte_unmap-on-an-not-mapped-pte.patch
mm-swapfile-fix-possible-data-races-of-inuse_pages.patch
mm-swapfile-fix-possible-data-races-of-inuse_pages-v3.patch
mm-swap-remove-swap_cache_info-statistics.patch
mm-vmscan-dont-try-to-reclaim-freed-folios.patch
mm-page_alloc-minor-clean-up-for-memmap_init_compound.patch
mm-madvise-minor-cleanup-for-swapin_walk_pmd_entry.patch
mm-mmapc-fix-missing-call-to-vm_unacct_memory-in-mmap_region.patch
mm-khugepaged-remove-unneeded-shmem_huge_enabled-check.patch
mm-khugepaged-stop-swapping-in-page-when-vm_fault_retry-occurs.patch
mm-khugepaged-trivial-typo-and-codestyle-cleanup.patch
mm-khugepaged-minor-cleanup-for-collapse_file.patch
mm-khugepaged-use-helper-macro-__attr_rw.patch
mm-khugepaged-remove-unneeded-return-value-of-khugepaged_add_pte_mapped_thp.patch
mm-khugepaged-try-to-free-transhuge-swapcache-when-possible.patch
