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 453D0C43334 for ; Wed, 29 Jun 2022 23:34:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232077AbiF2Xe0 (ORCPT ); Wed, 29 Jun 2022 19:34:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42044 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231848AbiF2XeI (ORCPT ); Wed, 29 Jun 2022 19:34:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 993F4101F6 for ; Wed, 29 Jun 2022 16:33:47 -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 C3ACC61E38 for ; Wed, 29 Jun 2022 23:33:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 206D2C34114; Wed, 29 Jun 2022 23:33:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1656545626; bh=SnXamDbb7Uec+8wlnT4xERSqfnVdjrlkolBc7V6jpJQ=; h=Date:To:From:Subject:From; b=mmBxoNFsN3gFzz+n0REyRHNDPlfYvB9fWnZGOj8QCxRdhW/9zuRzIpmTDfx60AW0E 0uAdvgWaoC+M+lzToAx0wbeinYZfYAxE/qLUdDgOD22zZOXbH8JV9Qo56/mvWA1+Et 4E5oAJu40fQf8QtbZd9Y/8PeSjtJRXeWTq4Xg57o= Date: Wed, 29 Jun 2022 16:33:45 -0700 To: mm-commits@vger.kernel.org, willy@infradead.org, rcampbell@nvidia.com, jglisse@redhat.com, jgg@nvidia.com, hch@lst.de, Felix.Kuehling@amd.com, david@redhat.com, apopple@nvidia.com, alex.sierra@amd.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-handling-non-lru-pages-returned-by-vm_normal_pages.patch added to mm-unstable branch Message-Id: <20220629233346.206D2C34114@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: handle Non-LRU pages returned by vm_normal_pages has been added to the -mm mm-unstable branch. Its filename is mm-handling-non-lru-pages-returned-by-vm_normal_pages.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-handling-non-lru-pages-returned-by-vm_normal_pages.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: Alex Sierra Subject: mm: handle Non-LRU pages returned by vm_normal_pages Date: Tue, 28 Jun 2022 22:54:15 -0500 With DEVICE_COHERENT, we'll soon have vm_normal_pages() return device-managed anonymous pages that are not LRU pages. Although they behave like normal pages for purposes of mapping in CPU page, and for COW. They do not support LRU lists, NUMA migration or THP. Callers to follow_page() currently don't expect ZONE_DEVICE pages, however, with DEVICE_COHERENT we might now return ZONE_DEVICE. Check for ZONE_DEVICE pages in applicable users of follow_page() as well. [akpm@linux-foundation.org: changelog edits from David] Link: https://lkml.kernel.org/r/20220629035426.20013-4-alex.sierra@amd.com Signed-off-by: Alex Sierra Acked-by: Felix Kuehling [v2] Reviewed-by: Alistair Popple [v6] Acked-by: David Hildenbrand Cc: Christoph Hellwig Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: Matthew Wilcox (Oracle) Cc: Ralph Campbell Signed-off-by: Andrew Morton --- fs/proc/task_mmu.c | 2 +- mm/huge_memory.c | 2 +- mm/khugepaged.c | 9 ++++++--- mm/ksm.c | 6 +++--- mm/madvise.c | 4 ++-- mm/memory.c | 9 ++++++++- mm/mempolicy.c | 2 +- mm/migrate.c | 4 ++-- mm/mlock.c | 2 +- mm/mprotect.c | 2 +- 10 files changed, 26 insertions(+), 16 deletions(-) --- a/fs/proc/task_mmu.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/fs/proc/task_mmu.c @@ -1800,7 +1800,7 @@ static struct page *can_gather_numa_stat return NULL; page = vm_normal_page(vma, addr, pte); - if (!page) + if (!page || is_zone_device_page(page)) return NULL; if (PageReserved(page)) --- a/mm/huge_memory.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/huge_memory.c @@ -2910,7 +2910,7 @@ static int split_huge_pages_pid(int pid, if (IS_ERR(page)) continue; - if (!page) + if (!page || is_zone_device_page(page)) continue; if (!is_transparent_hugepage(page)) --- a/mm/khugepaged.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/khugepaged.c @@ -618,7 +618,7 @@ static int __collapse_huge_page_isolate( goto out; } page = vm_normal_page(vma, address, pteval); - if (unlikely(!page)) { + if (unlikely(!page) || unlikely(is_zone_device_page(page))) { result = SCAN_PAGE_NULL; goto out; } @@ -1267,7 +1267,7 @@ static int khugepaged_scan_pmd(struct mm writable = true; page = vm_normal_page(vma, _address, pteval); - if (unlikely(!page)) { + if (unlikely(!page) || unlikely(is_zone_device_page(page))) { result = SCAN_PAGE_NULL; goto out_unmap; } @@ -1479,7 +1479,8 @@ void collapse_pte_mapped_thp(struct mm_s goto abort; page = vm_normal_page(vma, addr, *pte); - + if (WARN_ON_ONCE(page && is_zone_device_page(page))) + page = NULL; /* * Note that uprobe, debugger, or MAP_PRIVATE may change the * page table, but the new page will not be a subpage of hpage. @@ -1497,6 +1498,8 @@ void collapse_pte_mapped_thp(struct mm_s if (pte_none(*pte)) continue; page = vm_normal_page(vma, addr, *pte); + if (WARN_ON_ONCE(page && is_zone_device_page(page))) + goto abort; page_remove_rmap(page, vma, false); } --- a/mm/ksm.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/ksm.c @@ -475,7 +475,7 @@ static int break_ksm(struct vm_area_stru cond_resched(); page = follow_page(vma, addr, FOLL_GET | FOLL_MIGRATION | FOLL_REMOTE); - if (IS_ERR_OR_NULL(page)) + if (IS_ERR_OR_NULL(page) || is_zone_device_page(page)) break; if (PageKsm(page)) ret = handle_mm_fault(vma, addr, @@ -560,7 +560,7 @@ static struct page *get_mergeable_page(s goto out; page = follow_page(vma, addr, FOLL_GET); - if (IS_ERR_OR_NULL(page)) + if (IS_ERR_OR_NULL(page) || is_zone_device_page(page)) goto out; if (PageAnon(page)) { flush_anon_page(vma, page, addr); @@ -2311,7 +2311,7 @@ next_mm: if (ksm_test_exit(mm)) break; *page = follow_page(vma, ksm_scan.address, FOLL_GET); - if (IS_ERR_OR_NULL(*page)) { + if (IS_ERR_OR_NULL(*page) || is_zone_device_page(*page)) { ksm_scan.address += PAGE_SIZE; cond_resched(); continue; --- a/mm/madvise.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/madvise.c @@ -421,7 +421,7 @@ regular_page: continue; page = vm_normal_page(vma, addr, ptent); - if (!page) + if (!page || is_zone_device_page(page)) continue; /* @@ -639,7 +639,7 @@ static int madvise_free_pte_range(pmd_t } page = vm_normal_page(vma, addr, ptent); - if (!page) + if (!page || is_zone_device_page(page)) continue; /* --- a/mm/memory.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/memory.c @@ -633,6 +633,13 @@ struct page *vm_normal_page(struct vm_ar if (is_zero_pfn(pfn)) return NULL; if (pte_devmap(pte)) +/* + * NOTE: New uers of ZONE_DEVICE will not set pte_devmap() and will have + * refcounts incremented on their struct pages when they are inserted into + * PTEs, thus they are safe to return here. Legacy ZONE_DEVICE pages that set + * pte_devmap() do not have refcounts. Example of legacy ZONE_DEVICE is + * MEMORY_DEVICE_FS_DAX type in pmem or virtio_fs drivers. + */ return NULL; print_bad_pte(vma, addr, pte, NULL); @@ -4710,7 +4717,7 @@ static vm_fault_t do_numa_page(struct vm pte = pte_modify(old_pte, vma->vm_page_prot); page = vm_normal_page(vma, vmf->address, pte); - if (!page) + if (!page || is_zone_device_page(page)) goto out_map; /* TODO: handle PTE-mapped THP */ --- a/mm/mempolicy.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/mempolicy.c @@ -524,7 +524,7 @@ static int queue_pages_pte_range(pmd_t * if (!pte_present(*pte)) continue; page = vm_normal_page(vma, addr, *pte); - if (!page) + if (!page || is_zone_device_page(page)) continue; /* * vm_normal_page() filters out zero pages, but there might --- a/mm/migrate.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/migrate.c @@ -1630,7 +1630,7 @@ static int add_page_for_migration(struct goto out; err = -ENOENT; - if (!page) + if (!page || is_zone_device_page(page)) goto out; err = 0; @@ -1821,7 +1821,7 @@ static void do_pages_stat_array(struct m if (IS_ERR(page)) goto set_status; - if (page) { + if (page && !is_zone_device_page(page)) { err = page_to_nid(page); put_page(page); } else { --- a/mm/mlock.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/mlock.c @@ -333,7 +333,7 @@ static int mlock_pte_range(pmd_t *pmd, u if (!pte_present(*pte)) continue; page = vm_normal_page(vma, addr, *pte); - if (!page) + if (!page || is_zone_device_page(page)) continue; if (PageTransCompound(page)) continue; --- a/mm/mprotect.c~mm-handling-non-lru-pages-returned-by-vm_normal_pages +++ a/mm/mprotect.c @@ -95,7 +95,7 @@ static unsigned long change_pte_range(st continue; page = vm_normal_page(vma, addr, oldpte); - if (!page || PageKsm(page)) + if (!page || is_zone_device_page(page) || PageKsm(page)) continue; /* Also skip shared copy-on-write pages */ _ Patches currently in -mm which might be from alex.sierra@amd.com are mm-rename-is_pinnable_pages-to-is_pinnable_longterm_pages.patch mm-add-zone-device-coherent-type-memory-support.patch mm-handling-non-lru-pages-returned-by-vm_normal_pages.patch mm-add-device-coherent-vma-selection-for-memory-migration.patch drm-amdkfd-add-spm-support-for-svm.patch lib-test_hmm-add-ioctl-to-get-zone-device-type.patch lib-test_hmm-add-module-param-for-zone-device-type.patch lib-add-support-for-device-coherent-type-in-test_hmm.patch tools-update-hmm-test-to-support-device-coherent-type.patch tools-update-test_hmm-script-to-support-sp-config.patch tools-add-hmm-gup-tests-for-device-coherent-type.patch tools-add-selftests-to-hmm-for-cow-in-device-memory.patch