diff options
| author | Qi Zheng <zhengqi.arch@bytedance.com> | 2025-01-08 14:57:23 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-01-25 20:22:22 -0800 |
| commit | db6b435d731a8d82c38e558175db55466cb5832a (patch) | |
| tree | 6ad4b763d825245c7cd99ae9af18fb8c2fc29e13 /arch/um/include/asm | |
| parent | b7dcd539bfc7301b56fdaa6ebbb23752b670ee81 (diff) | |
mm: pgtable: introduce pagetable_dtor()
The pagetable_p*_dtor() are exactly the same except for the handling of
ptlock. If we make ptlock_free() handle the case where ptdesc->ptl is
NULL and remove VM_BUG_ON_PAGE() from pmd_ptlock_free(), we can unify
pagetable_p*_dtor() into one function. Let's introduce pagetable_dtor()
to do this.
Later, pagetable_dtor() will be moved to tlb_remove_ptdesc(), so that
ptlock and page table pages can be freed together (regardless of whether
RCU is used). This prevents the use-after-free problem where the ptlock
is freed immediately but the page table pages is freed later via RCU.
Link: https://lkml.kernel.org/r/47f44fff9dc68d9d9e9a0d6c036df275f820598a.1736317725.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> [s390]
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/um/include/asm')
| -rw-r--r-- | arch/um/include/asm/pgalloc.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/um/include/asm/pgalloc.h b/arch/um/include/asm/pgalloc.h index 04fb4e6969a4..f0af23c3aeb2 100644 --- a/arch/um/include/asm/pgalloc.h +++ b/arch/um/include/asm/pgalloc.h @@ -27,7 +27,7 @@ extern pgd_t *pgd_alloc(struct mm_struct *); #define __pte_free_tlb(tlb, pte, address) \ do { \ - pagetable_pte_dtor(page_ptdesc(pte)); \ + pagetable_dtor(page_ptdesc(pte)); \ tlb_remove_page_ptdesc((tlb), (page_ptdesc(pte))); \ } while (0) @@ -35,7 +35,7 @@ do { \ #define __pmd_free_tlb(tlb, pmd, address) \ do { \ - pagetable_pmd_dtor(virt_to_ptdesc(pmd)); \ + pagetable_dtor(virt_to_ptdesc(pmd)); \ tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pmd)); \ } while (0) @@ -43,7 +43,7 @@ do { \ #define __pud_free_tlb(tlb, pud, address) \ do { \ - pagetable_pud_dtor(virt_to_ptdesc(pud)); \ + pagetable_dtor(virt_to_ptdesc(pud)); \ tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pud)); \ } while (0) |