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 X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AD65C43461 for ; Wed, 21 Apr 2021 00:22:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE0176024A for ; Wed, 21 Apr 2021 00:22:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233928AbhDUAWi (ORCPT ); Tue, 20 Apr 2021 20:22:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:36052 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233863AbhDUAWi (ORCPT ); Tue, 20 Apr 2021 20:22:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C88B261409; Wed, 21 Apr 2021 00:22:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1618964525; bh=IWNCHNDee8FDaDFuD4487oUq2HTtDoN0pi2/8ulph00=; h=Date:From:To:Subject:From; b=X3ebIiOW08yfMbX0S41gSX6pdyiV0Umrt7KBobzoONEE0tO3Eyi5qRPR0VdtA94yA yZI/Bh0vDWwvyysDPy3jt3zIasXNfEJ0zVslcn+NzlaTVfRd13su+9/uScaZgxEous FfTPX0pboq2F7OjmQ1EiY3AVLiIr6lci+U7E5YOY= Date: Tue, 20 Apr 2021 17:22:04 -0700 From: akpm@linux-foundation.org To: david@redhat.com, mm-commits@vger.kernel.org, rppt@linux.ibm.com Subject: + =?US-ASCII?Q?mm-introduce-memfd=5Fsecret-system-call-to-create-secret-?= =?US-ASCII?Q?memory-areas-fix-2.patch?= added to -mm tree Message-ID: <20210421002204.HmKQb3VEO%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: secretmem/gup: don't check if page is secretmem without reference has been added to the -mm tree. Its filename is mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2.patch 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 and is updated there every 3-4 working days ------------------------------------------------------ From: Mike Rapoport Subject: secretmem/gup: don't check if page is secretmem without reference The check in gup_pte_range() whether a page belongs to a secretmem mapping is performed before grabbing the page reference. To avoid potential race move the check after try_grab_compound_head(). Link: https://lkml.kernel.org/r/20210420150049.14031-2-rppt@kernel.org Signed-off-by: Mike Rapoport Reviewed-by: David Hildenbrand Signed-off-by: Andrew Morton --- mm/gup.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/mm/gup.c~mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2 +++ a/mm/gup.c @@ -2080,13 +2080,15 @@ static int gup_pte_range(pmd_t pmd, unsi VM_BUG_ON(!pfn_valid(pte_pfn(pte))); page = pte_page(pte); - if (page_is_secretmem(page)) - goto pte_unmap; - head = try_grab_compound_head(page, 1, flags); if (!head) goto pte_unmap; + if (unlikely(page_is_secretmem(page))) { + put_compound_head(head, 1, flags); + goto pte_unmap; + } + if (unlikely(pte_val(pte) != pte_val(*ptep))) { put_compound_head(head, 1, flags); goto pte_unmap; _ Patches currently in -mm which might be from rppt@linux.ibm.com are mm-cma-rename-pf_memalloc_nocma-to-pf_memalloc_pin-fix.patch mmap-make-mlock_future_check-global.patch riscv-kconfig-make-direct-map-manipulation-options-depend-on-mmu.patch set_memory-allow-set_direct_map__noflush-for-multiple-pages.patch set_memory-allow-querying-whether-set_direct_map_-is-actually-enabled.patch mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas.patch mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix.patch mm-introduce-memfd_secret-system-call-to-create-secret-memory-areas-fix-2.patch pm-hibernate-disable-when-there-are-active-secretmem-users.patch arch-mm-wire-up-memfd_secret-system-call-where-relevant.patch arch-mm-wire-up-memfd_secret-system-call-where-relevant-fix.patch secretmem-test-add-basic-selftest-for-memfd_secret2.patch secretmem-test-add-basic-selftest-for-memfd_secret2-fix.patch secretmem-optimize-page_is_secretmem.patch