From patchwork Tue Aug 1 12:48:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13336666 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 D2D8AC001E0 for ; Tue, 1 Aug 2023 12:49:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232299AbjHAMtj (ORCPT ); Tue, 1 Aug 2023 08:49:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231844AbjHAMti (ORCPT ); Tue, 1 Aug 2023 08:49:38 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08BAC10EA for ; Tue, 1 Aug 2023 05:48:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690894131; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=RHFvfXcP0yrcIaYOdQEvaIRqqVbMZney2Vh1PcaD7Io=; b=fn75Dx0qzhAvlJAtUU7QOhNQHvqDlZYocg+SJbwePjD18/V5xDkBNE9WvCTtgAujR2VI3E 4e3cNH9vPmW/GsnEfs2jDycsIjNOVH306aR8aW4k/J1ZzYm5WUK2SBpGrUkzgjoWiMNf4L 8KnDzXnuN9qaSFyNsDQmhu5P/02zqfo= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-46-92PRgIToNqSHCN5sbvkKmg-1; Tue, 01 Aug 2023 08:48:50 -0400 X-MC-Unique: 92PRgIToNqSHCN5sbvkKmg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8876C3C14AA4; Tue, 1 Aug 2023 12:48:49 +0000 (UTC) Received: from t14s.fritz.box (unknown [10.39.193.232]) by smtp.corp.redhat.com (Postfix) with ESMTP id B7B1EC585A0; Tue, 1 Aug 2023 12:48:45 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, David Hildenbrand , Andrew Morton , Linus Torvalds , liubo , Peter Xu , Matthew Wilcox , Hugh Dickins , Jason Gunthorpe , John Hubbard , Mel Gorman , Shuah Khan , Paolo Bonzini Subject: [PATCH v2 0/8] smaps / mm/gup: fix gup_can_follow_protnone fallout Date: Tue, 1 Aug 2023 14:48:36 +0200 Message-ID: <20230801124844.278698-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This is agains mm/mm-unstable, but everything except patch #7 and #8 should apply on current master. Especially patch #1 and #2 should go upstream first, so we can let the other stuff mature a bit longer. Next attempt to handle the fallout of 474098edac26 ("mm/gup: replace FOLL_NUMA by gup_can_follow_protnone()") where I accidentially missed that follow_page() and smaps implicitly kept the FOLL_NUMA flag clear by not setting it if FOLL_FORCE is absent, to not trigger faults on PROT_NONE-mapped PTEs. Patch #1 fixes the known issues by reintroducing FOLL_NUMA as FOLL_HONOR_NUMA_FAULT and decoupling it from FOLL_FORCE. Patch #2 is a cleanup that I think actually fixes some corner cases, so I added a Fixes: tag. Patch #3 makes KVM explicitly set FOLL_HONOR_NUMA_FAULT in the single case where it is required, and documents the situation. Patch #4 then stops implicitly setting FOLL_HONOR_NUMA_FAULT. But note that for FOLL_WRITE we always implicitly honor NUMA hinting faults. Patch #5 and patch #6 cleanup some comments. Patch #7 improves the KVM functional tests such that patch #8 can actually check for one of the known issues: KSM no longer working on PROT_NONE mappings on x86-64 with CONFIG_NUMA_BALANCING. Cc: Andrew Morton Cc: Linus Torvalds Cc: liubo Cc: Peter Xu Cc: Matthew Wilcox Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: John Hubbard Cc: Mel Gorman Cc: Shuah Khan Cc: Paolo Bonzini David Hildenbrand (8): mm/gup: reintroduce FOLL_NUMA as FOLL_HONOR_NUMA_FAULT smaps: use vm_normal_page_pmd() instead of follow_trans_huge_pmd() kvm: explicitly set FOLL_HONOR_NUMA_FAULT in hva_to_pfn_slow() mm/gup: don't implicitly set FOLL_HONOR_NUMA_FAULT pgtable: improve pte_protnone() comment mm/huge_memory: remove stale NUMA hinting comment from follow_trans_huge_pmd() selftest/mm: ksm_functional_tests: test in mmap_and_merge_range() if anything got merged selftest/mm: ksm_functional_tests: Add PROT_NONE test fs/proc/task_mmu.c | 3 +- include/linux/mm.h | 21 +++- include/linux/mm_types.h | 9 ++ include/linux/pgtable.h | 16 ++- mm/gup.c | 23 +++- mm/huge_memory.c | 3 +- .../selftests/mm/ksm_functional_tests.c | 106 ++++++++++++++++-- virt/kvm/kvm_main.c | 13 ++- 8 files changed, 164 insertions(+), 30 deletions(-)