The patch titled Subject: riscv: use an atomic xchg in pudp_huge_get_and_clear() has been added to the -mm mm-new branch. Its filename is riscv-use-an-atomic-xchg-in-pudp_huge_get_and_clear.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Alexandre Ghiti alexghiti@rivosinc.com Subject: riscv: use an atomic xchg in pudp_huge_get_and_clear() Date: Thu, 14 Aug 2025 12:06:14 +0000

Make sure we return the right pud value and not a value that could have been overwritten in between by a different core.

Link: https://lkml.kernel.org/r/20250814-dev-alex-thp_pud_xchg-v1-1-b4704dfae206@r... Fixes: c3cc2a4a3a23 ("riscv: Add support for PUD THP") Signed-off-by: Alexandre Ghiti alexghiti@rivosinc.com Cc: Andrew Donnellan ajd@linux.ibm.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

arch/riscv/include/asm/pgtable.h | 11 +++++++++++ 1 file changed, 11 insertions(+)

--- a/arch/riscv/include/asm/pgtable.h~riscv-use-an-atomic-xchg-in-pudp_huge_get_and_clear +++ a/arch/riscv/include/asm/pgtable.h @@ -942,6 +942,17 @@ static inline int pudp_test_and_clear_yo return ptep_test_and_clear_young(vma, address, (pte_t *)pudp); }

+#define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR +static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, + unsigned long address, pud_t *pudp) +{ + pud_t pud = __pud(atomic_long_xchg((atomic_long_t *)pudp, 0)); + + page_table_check_pud_clear(mm, pud); + + return pud; +} + static inline int pud_young(pud_t pud) { return pte_young(pud_pte(pud)); _

Patches currently in -mm which might be from alexghiti@rivosinc.com are

selftests-damon-fix-damon-selftests-by-installing-_commonsh.patch riscv-use-an-atomic-xchg-in-pudp_huge_get_and_clear.patch