From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9360C7EE25 for ; Fri, 9 Jun 2023 20:12:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231318AbjFIUMK (ORCPT ); Fri, 9 Jun 2023 16:12:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231174AbjFIULw (ORCPT ); Fri, 9 Jun 2023 16:11:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCFA43A81 for ; Fri, 9 Jun 2023 13:11:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5AB6865BAC for ; Fri, 9 Jun 2023 20:11:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1E5DC433EF; Fri, 9 Jun 2023 20:11:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1686341509; bh=4dbZi3FcgLcq1jXGiNnize73yBHnBr+ztXOySgs6ABw=; h=Date:To:From:Subject:From; b=mD1d26PSqEColWrSilGJhQ/lbi2VudDVWLkGs7PMRUqVjs9WwYoNLEIsmSwmtilsb aOeit3M5XzHHsFwrkDSufGQOnMEDrqnBeaw85ecTZUbokwqDPmJtdQPLz0vtU4Fc4C MO5KObJ9ZMhzoSNgRsN/HJdvgmLfkWJS3jF7en+Y= Date: Fri, 09 Jun 2023 13:11:49 -0700 To: mm-commits@vger.kernel.org, zhengqi.arch@bytedance.com, zackr@vmware.com, yuzhao@google.com, ying.huang@intel.com, willy@infradead.org, will@kernel.org, thomas.hellstrom@linux.intel.com, surenb@google.com, steven.price@arm.com, song@kernel.org, sj@kernel.org, shy828301@gmail.com, ryan.roberts@arm.com, rppt@kernel.org, rcampbell@nvidia.com, peterz@infradead.org, peterx@redhat.com, pasha.tatashin@soleen.com, naoya.horiguchi@nec.com, minchan@kernel.org, mike.kravetz@oracle.com, mgorman@techsingularity.net, lstoakes@gmail.com, linmiaohe@huawei.com, kirill.shutemov@linux.intel.com, jgg@ziepe.ca, ira.weiny@intel.com, hch@infradead.org, david@redhat.com, christophe.leroy@csgroup.eu, axelrasmussen@google.com, apopple@nvidia.com, anshuman.khandual@arm.com, hughd@google.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-huge_memory-split-huge-pmd-under-one-pte_offset_map.patch added to mm-unstable branch Message-Id: <20230609201149.A1E5DC433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/huge_memory: split huge pmd under one pte_offset_map() has been added to the -mm mm-unstable branch. Its filename is mm-huge_memory-split-huge-pmd-under-one-pte_offset_map.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-huge_memory-split-huge-pmd-under-one-pte_offset_map.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Hugh Dickins Subject: mm/huge_memory: split huge pmd under one pte_offset_map() Date: Thu, 8 Jun 2023 18:41:31 -0700 (PDT) __split_huge_zero_page_pmd() use a single pte_offset_map() to sweep the extent: it's already under pmd_lock(), so this is no worse for latency; and since it's supposed to have full control of the just-withdrawn page table, here choose to VM_BUG_ON if it were to fail. And please don't increment haddr by PAGE_SIZE, that should remain huge aligned: declare a separate addr (not a bugfix, but it was deceptive). __split_huge_pmd_locked() likewise (but it had declared a separate addr); and change its BUG_ON(!pte_none) to VM_BUG_ON, for consistency with zero (those deposited page tables are sometimes victims of random corruption). Link: https://lkml.kernel.org/r/90cbed7f-90d9-b779-4a46-d2485baf9595@google.com Signed-off-by: Hugh Dickins Reviewed-by: Yang Shi Cc: Alistair Popple Cc: Anshuman Khandual Cc: Axel Rasmussen Cc: Christophe Leroy Cc: Christoph Hellwig Cc: David Hildenbrand Cc: "Huang, Ying" Cc: Ira Weiny Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Lorenzo Stoakes Cc: Matthew Wilcox Cc: Mel Gorman Cc: Miaohe Lin Cc: Mike Kravetz Cc: Mike Rapoport (IBM) Cc: Minchan Kim Cc: Naoya Horiguchi Cc: Pavel Tatashin Cc: Peter Xu Cc: Peter Zijlstra Cc: Qi Zheng Cc: Ralph Campbell Cc: Ryan Roberts Cc: SeongJae Park Cc: Song Liu Cc: Steven Price Cc: Suren Baghdasaryan Cc: Thomas Hellström Cc: Will Deacon Cc: Yu Zhao Cc: Zack Rusin Signed-off-by: Andrew Morton --- mm/huge_memory.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-split-huge-pmd-under-one-pte_offset_map +++ a/mm/huge_memory.c @@ -2037,6 +2037,8 @@ static void __split_huge_zero_page_pmd(s struct mm_struct *mm = vma->vm_mm; pgtable_t pgtable; pmd_t _pmd, old_pmd; + unsigned long addr; + pte_t *pte; int i; /* @@ -2052,17 +2054,20 @@ static void __split_huge_zero_page_pmd(s pgtable = pgtable_trans_huge_withdraw(mm, pmd); pmd_populate(mm, &_pmd, pgtable); - for (i = 0; i < HPAGE_PMD_NR; i++, haddr += PAGE_SIZE) { - pte_t *pte, entry; - entry = pfn_pte(my_zero_pfn(haddr), vma->vm_page_prot); + pte = pte_offset_map(&_pmd, haddr); + VM_BUG_ON(!pte); + for (i = 0, addr = haddr; i < HPAGE_PMD_NR; i++, addr += PAGE_SIZE) { + pte_t entry; + + entry = pfn_pte(my_zero_pfn(addr), vma->vm_page_prot); entry = pte_mkspecial(entry); if (pmd_uffd_wp(old_pmd)) entry = pte_mkuffd_wp(entry); - pte = pte_offset_map(&_pmd, haddr); VM_BUG_ON(!pte_none(*pte)); - set_pte_at(mm, haddr, pte, entry); - pte_unmap(pte); + set_pte_at(mm, addr, pte, entry); + pte++; } + pte_unmap(pte - 1); smp_wmb(); /* make pte visible before pmd */ pmd_populate(mm, pmd, pgtable); } @@ -2077,6 +2082,7 @@ static void __split_huge_pmd_locked(stru bool young, write, soft_dirty, pmd_migration = false, uffd_wp = false; bool anon_exclusive = false, dirty = false; unsigned long addr; + pte_t *pte; int i; VM_BUG_ON(haddr & ~HPAGE_PMD_MASK); @@ -2205,8 +2211,10 @@ static void __split_huge_pmd_locked(stru pgtable = pgtable_trans_huge_withdraw(mm, pmd); pmd_populate(mm, &_pmd, pgtable); + pte = pte_offset_map(&_pmd, haddr); + VM_BUG_ON(!pte); for (i = 0, addr = haddr; i < HPAGE_PMD_NR; i++, addr += PAGE_SIZE) { - pte_t entry, *pte; + pte_t entry; /* * Note that NUMA hinting access restrictions are not * transferred to avoid any possibility of altering @@ -2249,11 +2257,11 @@ static void __split_huge_pmd_locked(stru entry = pte_mkuffd_wp(entry); page_add_anon_rmap(page + i, vma, addr, false); } - pte = pte_offset_map(&_pmd, addr); - BUG_ON(!pte_none(*pte)); + VM_BUG_ON(!pte_none(*pte)); set_pte_at(mm, addr, pte, entry); - pte_unmap(pte); + pte++; } + pte_unmap(pte - 1); if (!pmd_migration) page_remove_rmap(page, vma, true); _ Patches currently in -mm which might be from hughd@google.com are arm-allow-pte_offset_map-to-fail.patch arm64-allow-pte_offset_map-to-fail.patch arm64-hugetlb-pte_alloc_huge-pte_offset_huge.patch ia64-hugetlb-pte_alloc_huge-pte_offset_huge.patch m68k-allow-pte_offset_map-to-fail.patch microblaze-allow-pte_offset_map-to-fail.patch mips-update_mmu_cache-can-replace-__update_tlb.patch mips-update_mmu_cache-can-replace-__update_tlb-fix.patch parisc-add-pte_unmap-to-balance-get_ptep.patch parisc-unmap_uncached_pte-use-pte_offset_kernel.patch parisc-hugetlb-pte_alloc_huge-pte_offset_huge.patch powerpc-kvmppc_unmap_free_pmd-pte_offset_kernel.patch powerpc-allow-pte_offset_map-to-fail.patch powerpc-hugetlb-pte_alloc_huge.patch riscv-hugetlb-pte_alloc_huge-pte_offset_huge.patch s390-allow-pte_offset_map_lock-to-fail.patch s390-gmap-use-pte_unmap_unlock-not-spin_unlock.patch sh-hugetlb-pte_alloc_huge-pte_offset_huge.patch sparc-hugetlb-pte_alloc_huge-pte_offset_huge.patch sparc-allow-pte_offset_map-to-fail.patch sparc-iounit-and-iommu-use-pte_offset_kernel.patch x86-allow-get_locked_pte-to-fail.patch x86-sme_populate_pgd-use-pte_offset_kernel.patch xtensa-add-pte_unmap-to-balance-pte_offset_map.patch mm-use-pmdp_get_lockless-without-surplus-barrier.patch mm-migrate-remove-cruft-from-migration_entry_waits.patch mm-pgtable-kmap_local_page-instead-of-kmap_atomic.patch mm-pgtable-allow-pte_offset_map-to-fail.patch mm-filemap-allow-pte_offset_map_lock-to-fail.patch mm-page_vma_mapped-delete-bogosity-in-page_vma_mapped_walk.patch mm-page_vma_mapped-reformat-map_pte-with-less-indentation.patch mm-page_vma_mapped-pte_offset_map_nolock-not-pte_lockptr.patch mm-pagewalkers-action_again-if-pte_offset_map_lock-fails.patch mm-pagewalk-walk_pte_range-allow-for-pte_offset_map.patch mm-vmwgfx-simplify-pmd-pud-mapping-dirty-helpers.patch mm-vmalloc-vmalloc_to_page-use-pte_offset_kernel.patch mm-hmm-retry-if-pte_offset_map-fails.patch mm-userfaultfd-retry-if-pte_offset_map-fails.patch mm-userfaultfd-allow-pte_offset_map_lock-to-fail.patch mm-debug_vm_pgtablepage_table_check-warn-pte-map-fails.patch mm-various-give-up-if-pte_offset_map-fails.patch mm-mprotect-delete-pmd_none_or_clear_bad_unless_trans_huge.patch mm-mremap-retry-if-either-pte_offset_map_lock-fails.patch mm-madvise-clean-up-pte_offset_map_lock-scans.patch mm-madvise-clean-up-force_shm_swapin_readahead.patch mm-swapoff-allow-pte_offset_map-to-fail.patch mm-mglru-allow-pte_offset_map_nolock-to-fail.patch mm-migrate_device-allow-pte_offset_map_lock-to-fail.patch mm-gup-remove-foll_split_pmd-use-of-pmd_trans_unstable.patch mm-huge_memory-split-huge-pmd-under-one-pte_offset_map.patch mm-khugepaged-allow-pte_offset_map-to-fail.patch mm-memory-allow-pte_offset_map-to-fail.patch mm-memory-handle_pte_fault-use-pte_offset_map_nolock.patch mm-pgtable-delete-pmd_trans_unstable-and-friends.patch mm-swap-swap_vma_readahead-do-the-pte_offset_map.patch perf-core-allow-pte_offset_map-to-fail.patch