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 7368DC4167B for ; Tue, 29 Nov 2022 21:23:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235900AbiK2VXZ (ORCPT ); Tue, 29 Nov 2022 16:23:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237083AbiK2VXW (ORCPT ); Tue, 29 Nov 2022 16:23:22 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E36DC1DF28 for ; Tue, 29 Nov 2022 13:23:12 -0800 (PST) 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 ams.source.kernel.org (Postfix) with ESMTPS id 9E962B8191D for ; Tue, 29 Nov 2022 21:23:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42FDAC433D6; Tue, 29 Nov 2022 21:23:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1669756990; bh=0mEpvMp8Z/cQD/op0y1NrukRdIkd5mdQ5V8chlWVDsY=; h=Date:To:From:Subject:From; b=BQg2N249yTS+VoeCpYBnwmDbPSCCjyMcWGcLwu9CK5DJBWxFB0EG21EouPGetFCov DZ/XGu2nAmrTcJxr4ZNLKidmMLInI/DDQ98krS8tJ0UkGw4UW3WMM35HNEH2koxEdW skmGUJlmqzXGmr6BbQGJ3CDcDNvSfZuThejECtSQ= Date: Tue, 29 Nov 2022 13:23:09 -0800 To: mm-commits@vger.kernel.org, songmuchun@bytedance.com, riel@surriel.com, nadav.amit@gmail.com, mike.kravetz@oracle.com, linmiaohe@huawei.com, jthoughton@google.com, jannh@google.com, aarcange@redhat.com, peterx@redhat.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare.patch added to mm-unstable branch Message-Id: <20221129212310.42FDAC433D6@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/hugetlb: make page_vma_mapped_walk() safe to pmd unshare has been added to the -mm mm-unstable branch. Its filename is mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare.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: Peter Xu Subject: mm/hugetlb: make page_vma_mapped_walk() safe to pmd unshare Date: Tue, 29 Nov 2022 14:35:25 -0500 Since page_vma_mapped_walk() walks the pgtable, it needs the vma lock to make sure the pgtable page will not be freed concurrently. Link: https://lkml.kernel.org/r/20221129193526.3588187-10-peterx@redhat.com Signed-off-by: Peter Xu Cc: Andrea Arcangeli Cc: James Houghton Cc: Jann Horn Cc: Miaohe Lin Cc: Mike Kravetz Cc: Muchun Song Cc: Nadav Amit Cc: Rik van Riel Signed-off-by: Andrew Morton --- include/linux/rmap.h | 4 ++++ mm/page_vma_mapped.c | 5 ++++- 2 files changed, 8 insertions(+), 1 deletion(-) --- a/include/linux/rmap.h~mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare +++ a/include/linux/rmap.h @@ -13,6 +13,7 @@ #include #include #include +#include /* * The anon_vma heads a list of private "related" vmas, to scan if @@ -408,6 +409,9 @@ static inline void page_vma_mapped_walk_ pte_unmap(pvmw->pte); if (pvmw->ptl) spin_unlock(pvmw->ptl); + /* This needs to be after unlock of the spinlock */ + if (is_vm_hugetlb_page(pvmw->vma)) + hugetlb_vma_unlock_read(pvmw->vma); } bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw); --- a/mm/page_vma_mapped.c~mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare +++ a/mm/page_vma_mapped.c @@ -169,10 +169,13 @@ bool page_vma_mapped_walk(struct page_vm if (pvmw->pte) return not_found(pvmw); + hugetlb_vma_lock_read(vma); /* when pud is not present, pte will be NULL */ pvmw->pte = huge_pte_offset(mm, pvmw->address, size); - if (!pvmw->pte) + if (!pvmw->pte) { + hugetlb_vma_unlock_read(vma); return false; + } pvmw->ptl = huge_pte_lock(hstate, mm, pvmw->pte); if (!check_pte(pvmw)) _ Patches currently in -mm which might be from peterx@redhat.com are mm-migrate-fix-read-only-page-got-writable-when-recover-pte.patch mm-always-compile-in-pte-markers.patch mm-use-pte-markers-for-swap-errors.patch mm-uffd-sanity-check-write-bit-for-uffd-wp-protected-ptes.patch selftests-vm-use-memfd-for-hugepage-mmap-test.patch mm-thp-re-apply-mkdirty-for-small-pages-after-split.patch mm-hugetlb-let-vma_offset_start-to-return-start.patch mm-hugetlb-dont-wait-for-migration-entry-during-follow-page.patch mm-hugetlb-document-huge_pte_offset-usage.patch mm-hugetlb-move-swap-entry-handling-into-vma-lock-when-faulted.patch mm-hugetlb-make-userfaultfd_huge_must_wait-safe-to-pmd-unshare.patch mm-hugetlb-make-hugetlb_follow_page_mask-safe-to-pmd-unshare.patch mm-hugetlb-make-follow_hugetlb_page-safe-to-pmd-unshare.patch mm-hugetlb-make-walk_hugetlb_range-safe-to-pmd-unshare.patch mm-hugetlb-make-page_vma_mapped_walk-safe-to-pmd-unshare.patch mm-hugetlb-introduce-hugetlb_walk.patch