From: Barry Song v-songbaohua@oppo.com
mainline inclusion from mainline-v6.10-rc3 commit 6434e69814b159608a23135ca2be36024f402717 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IAIHQO
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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We are passing a huge nr to __clear_young_dirty_ptes() right now. While we should pass the number of pages, we are actually passing CONT_PTE_SIZE. This is causing lots of crashes of MADV_FREE, panic oops could vary everytime.
Link: https://lkml.kernel.org/r/20240524005444.135417-1-21cnbao@gmail.com Fixes: 89e86854fb0a ("mm/arm64: override clear_young_dirty_ptes() batch helper") Signed-off-by: Barry Song v-songbaohua@oppo.com Reviewed-by: Baolin Wang baolin.wang@linux.alibaba.com Acked-by: Lance Yang ioworker0@gmail.com Acked-by: David Hildenbrand david@redhat.com Acked-by: Chris Li chrisl@kernel.org Cc: Barry Song 21cnbao@gmail.com Cc: Ryan Roberts ryan.roberts@arm.com Cc: Jeff Xie xiehuan09@gmail.com Cc: Kefeng Wang wangkefeng.wang@huawei.com Cc: Michal Hocko mhocko@suse.com Cc: Minchan Kim minchan@kernel.org Cc: Muchun Song songmuchun@bytedance.com Cc: Peter Xu peterx@redhat.com Cc: Yang Shi shy828301@gmail.com Cc: Yin Fengwei fengwei.yin@intel.com Cc: Zach O'Keefe zokeefe@google.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Liu Shixin liushixin2@huawei.com --- arch/arm64/mm/contpte.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index 9f9486de0004..a3edced29ac1 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -376,7 +376,7 @@ void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma, * clearing access/dirty for the whole block. */ unsigned long start = addr; - unsigned long end = start + nr; + unsigned long end = start + nr * PAGE_SIZE;
if (pte_cont(__ptep_get(ptep + nr - 1))) end = ALIGN(end, CONT_PTE_SIZE); @@ -386,7 +386,7 @@ void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma, ptep = contpte_align_down(ptep); }
- __clear_young_dirty_ptes(vma, start, ptep, end - start, flags); + __clear_young_dirty_ptes(vma, start, ptep, (end - start) / PAGE_SIZE, flags); } EXPORT_SYMBOL_GPL(contpte_clear_young_dirty_ptes);