From patchwork Tue Apr 11 14:15:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81991 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2614344vqo; Tue, 11 Apr 2023 07:22:32 -0700 (PDT) X-Google-Smtp-Source: AKy350Z6evET1yf8LJ04XAxXzGf1Rp/IFRgSzzMJnQLQd/oLpDQFbLrz7cXUiylUvfIqPgt9/o0o X-Received: by 2002:a05:6a20:85a4:b0:d9:2827:b65a with SMTP id s36-20020a056a2085a400b000d92827b65amr10604255pzd.5.1681222952088; Tue, 11 Apr 2023 07:22:32 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681222952; cv=none; d=google.com; s=arc-20160816; b=okzkOGYZubsgBG+z3cv7SN5nVUIEPJmtxj2YTCkVW+YZ+DCc3eOTHj8Hj08FbAqyQ8 LNoyu13TQ3mMWATUWK+j/A0TyaamIoEfjRkf9XFCiuKlG1LEwCiHiFUd+iY1bJR0iMeH yahurni5ElNRUH0WFd56uVChNwF1vDvLQ+7gLlXrdgrCqFaa4aNjV+qAc4FaJ3zO6ZJs g1KIDcy3yq9eG64wSruunbUecPxvsoGmEIU3cKBZWNNHd5qvSaH0tb2wxd/KhcRyXm1l SLH+TeaXIKbbgWk7efU9HnkmQT0uR28Ykz7ABQioMhViNfAMXm3AQ/4F0Cb2lYZ+c/dZ cQbg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=2z0ZWpIzSXqyEF2KVa3LzGMQGesZiayZZfA3zEW/CRA=; b=eL2oOBe8A1jkL/2WHoGTV5JDIxH6IaYwRxREw2EL8NO1RuJ1VNpcQ4Q5t4XFDolRR4 Vg3d6eV9ypNv13+armEBUh6jcGM1peSjUCtNopMh95YZnReBV4olqP1SLeZGZZAouAXB NJIB6iApUxgqz+qQi94SRiDgFxE8sScvC/EDea+dBA9a8mOIvGEc+5qsmkGEmtOa0Em9 XbALs56RQmfXrsRRXMcDnTpua64mksnsTz/LIyIIoDAtNaRMwYsJbnMPka+4ijaWTEms sfcCtyPCJwC/ZE0sBf6Cf3wNYXphLLvuX97h44a/FEjcTiaVikr7Pjl3V1hEudwD0GcM u5IQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=Xy9GjChj; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id 20-20020a630c54000000b004fb8f5e1a8dsi12715467pgm.111.2023.04.11.07.22.17; Tue, 11 Apr 2023 07:22:32 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=Xy9GjChj; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230247AbjDKOR1 (ORCPT + 99 others); Tue, 11 Apr 2023 10:17:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229999AbjDKORP (ORCPT ); Tue, 11 Apr 2023 10:17:15 -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 679D23C02 for ; Tue, 11 Apr 2023 07:15:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222547; 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: in-reply-to:in-reply-to:references:references; bh=2z0ZWpIzSXqyEF2KVa3LzGMQGesZiayZZfA3zEW/CRA=; b=Xy9GjChjILvayFNCTq5emGUkduekwy5mIXtO6k9hLfmvQKbK5B9CKsV2qU6UWnYYA7lFI9 JuOodzsWWjtgtOG1cdWFHxInrKc7V2286rkD7jg30PLOXnN7uuCvOy3RuOgWmJXjOq7WWE Te/ufZd6UuTkApDd4/CpwTMzLGty4XA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-120-KgYERSC9NFGw5yGLnWJkng-1; Tue, 11 Apr 2023 10:15:46 -0400 X-MC-Unique: KgYERSC9NFGw5yGLnWJkng-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AFDC888718F; Tue, 11 Apr 2023 14:15:37 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 50396400F281; Tue, 11 Apr 2023 14:15:36 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 1/6] selftests/mm: reuse read_pmd_pagesize() in COW selftest Date: Tue, 11 Apr 2023 16:15:24 +0200 Message-Id: <20230411141529.428991-3-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890038293615506?= X-GMAIL-MSGID: =?utf-8?q?1762890038293615506?= The COW selftest can deal with THP not being configured. So move error handling of read_pmd_pagesize() into the callers such that we can reuse it in the COW selftest. Signed-off-by: David Hildenbrand --- tools/testing/selftests/mm/cow.c | 33 +++---------------- tools/testing/selftests/mm/khugepaged.c | 4 +++ tools/testing/selftests/mm/soft-dirty.c | 3 ++ .../selftests/mm/split_huge_page_test.c | 4 +++ tools/testing/selftests/mm/vm_util.c | 4 +-- 5 files changed, 17 insertions(+), 31 deletions(-) diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c index 0eb2e8180aa5..dc9d6fe86028 100644 --- a/tools/testing/selftests/mm/cow.c +++ b/tools/testing/selftests/mm/cow.c @@ -45,34 +45,6 @@ static size_t hugetlbsizes[10]; static int gup_fd; static bool has_huge_zeropage; -static void detect_thpsize(void) -{ - int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", - O_RDONLY); - size_t size = 0; - char buf[15]; - int ret; - - if (fd < 0) - return; - - ret = pread(fd, buf, sizeof(buf), 0); - if (ret > 0 && ret < sizeof(buf)) { - buf[ret] = 0; - - size = strtoul(buf, NULL, 10); - if (size < pagesize) - size = 0; - if (size > 0) { - thpsize = size; - ksft_print_msg("[INFO] detected THP size: %zu KiB\n", - thpsize / 1024); - } - } - - close(fd); -} - static void detect_huge_zeropage(void) { int fd = open("/sys/kernel/mm/transparent_hugepage/use_zero_page", @@ -1741,7 +1713,10 @@ int main(int argc, char **argv) int err; pagesize = getpagesize(); - detect_thpsize(); + thpsize = read_pmd_pagesize(); + if (thpsize) + ksft_print_msg("[INFO] detected THP size: %zu KiB\n", + thpsize / 1024); detect_hugetlbsizes(); detect_huge_zeropage(); diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c index 64126c8cd561..97adc0f34f9c 100644 --- a/tools/testing/selftests/mm/khugepaged.c +++ b/tools/testing/selftests/mm/khugepaged.c @@ -1476,6 +1476,10 @@ int main(int argc, const char **argv) page_size = getpagesize(); hpage_pmd_size = read_pmd_pagesize(); + if (!hpage_pmd_size) { + printf("Reading PMD pagesize failed"); + exit(EXIT_FAILURE); + } hpage_pmd_nr = hpage_pmd_size / page_size; default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1; diff --git a/tools/testing/selftests/mm/soft-dirty.c b/tools/testing/selftests/mm/soft-dirty.c index 21d8830c5f24..cc5f144430d4 100644 --- a/tools/testing/selftests/mm/soft-dirty.c +++ b/tools/testing/selftests/mm/soft-dirty.c @@ -80,6 +80,9 @@ static void test_hugepage(int pagemap_fd, int pagesize) int i, ret; size_t hpage_len = read_pmd_pagesize(); + if (!hpage_len) + ksft_exit_fail_msg("Reading PMD pagesize failed"); + map = memalign(hpage_len, hpage_len); if (!map) ksft_exit_fail_msg("memalign failed\n"); diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c index 76e1c36dd9e5..1dc5804b8b2b 100644 --- a/tools/testing/selftests/mm/split_huge_page_test.c +++ b/tools/testing/selftests/mm/split_huge_page_test.c @@ -300,6 +300,10 @@ int main(int argc, char **argv) pagesize = getpagesize(); pageshift = ffs(pagesize) - 1; pmd_pagesize = read_pmd_pagesize(); + if (!pmd_pagesize) { + printf("Reading PMD pagesize failed\n"); + exit(EXIT_FAILURE); + } split_pmd_thp(); split_pte_mapped_thp(); diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index 40e795624ff3..8dc74dd022c2 100644 --- a/tools/testing/selftests/mm/vm_util.c +++ b/tools/testing/selftests/mm/vm_util.c @@ -84,12 +84,12 @@ uint64_t read_pmd_pagesize(void) fd = open(PMD_SIZE_FILE_PATH, O_RDONLY); if (fd == -1) - ksft_exit_fail_msg("Open hpage_pmd_size failed\n"); + return 0; num_read = read(fd, buf, 19); if (num_read < 1) { close(fd); - ksft_exit_fail_msg("Read hpage_pmd_size failed\n"); + return 0; } buf[num_read] = '\0'; close(fd); From patchwork Tue Apr 11 14:15:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81994 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2616082vqo; Tue, 11 Apr 2023 07:25:10 -0700 (PDT) X-Google-Smtp-Source: AKy350ZNGTW+rQnRRxwU5yUQeqSba9eaJrC4llLgwVny8TGQekB5ogW/lNiI8Di1Rqg39Wy8/TUz X-Received: by 2002:a17:90a:a58a:b0:246:d13c:c027 with SMTP id b10-20020a17090aa58a00b00246d13cc027mr3763436pjq.24.1681223110257; Tue, 11 Apr 2023 07:25:10 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681223110; cv=none; d=google.com; s=arc-20160816; b=bwA4HIrhSUePhshNsc12mXlUGMsh8Fq6cweve/8DGhMB4ifwfIBw6JemBEA74VppR1 ClbmChzEAZbW3rSyKg67Lla5T0ZUK1v0MxEMthF4tdiegGz62kCLDxs4NCEdhW7EYKfm nZj/TiaMD6GaViJEGAF2c2SckIYQOlfUhEz8hQxYYudkFEwzOhTzfpl+Lmt1+1+AE1BF zKGEcnquCgVCiFvZrW4sIjL8/5VFn7jDUPRnBVPTF0mxB2KNZ6XAEjBIsr2ngz1TKusM s+AIIDKRGBQ0DUkeI+HfVJiJbLrA63TKfQFWtRbxW3ohtxJdrmETvJABkJfRsocCo8Ni qjLg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=kiblhRIXN5QVGSvHoajKRlNDk3I/DcpYGGNog0nXOOg=; b=Jt6pRbMeTbZhi5W668IKrTY24mTga6uhh4tF72/WUbFHFbs6qiTR+1Fn+g+Hp0iMi0 fazBm0VNxBHirgIIJYHwGG6ycFvZM24Jci5UqH9UNYF9cz3LDKqkiOoprO5imVqB2A0b rIk3JkEEV2OFHfCThMVlg1pELs5Ni7KTCZXiw+IQ837iMhklG8cTKyn3VwWIDE2oZI+a 4oKlDTdchSAN72Z32LoHQ9uWESWg4KAkzZyqDvv6YCigCnXgXOFmKixB+DGIyf8RNLAK X+B5k3gwnS8KDzWDVPes2e+P1uzKi9VHrmkpaSaWRFlhJ4LSjkkHob3hWM1MFneJFQKG lMkg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=HtN8lnPW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id lk13-20020a17090b33cd00b0023def94be5esi12260895pjb.20.2023.04.11.07.24.57; Tue, 11 Apr 2023 07:25:10 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=HtN8lnPW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230307AbjDKORp (ORCPT + 99 others); Tue, 11 Apr 2023 10:17:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48236 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230234AbjDKORY (ORCPT ); Tue, 11 Apr 2023 10:17:24 -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 90EA649F0 for ; Tue, 11 Apr 2023 07:15:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222550; 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: in-reply-to:in-reply-to:references:references; bh=kiblhRIXN5QVGSvHoajKRlNDk3I/DcpYGGNog0nXOOg=; b=HtN8lnPWeCuZ7YO9jgpGPOKaTqWWlCX/QIOtepeQaeNprNfDoeku+Eqz5ltsV+CsIxVd4R YaDtWZNnVmxpPwL10lGr6iZIRL2q79VdCgO7CHftFGJJYGtJpW8Gz030lJ757VS7yxbkvr 150HHal8zUfk1nIWyh595GVuukkTynE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-306-jhitVNstOv2k9zuv4EVEVA-1; Tue, 11 Apr 2023 10:15:47 -0400 X-MC-Unique: jhitVNstOv2k9zuv4EVEVA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4C84B889067; Tue, 11 Apr 2023 14:15:39 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id F1939400F286; Tue, 11 Apr 2023 14:15:37 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 2/6] selftests/mm: mkdirty: test behavior of (pte|pmd)_mkdirty on VMAs without write permissions Date: Tue, 11 Apr 2023 16:15:25 +0200 Message-Id: <20230411141529.428991-4-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890204393540605?= X-GMAIL-MSGID: =?utf-8?q?1762890204393540605?= Let's add some tests that trigger (pte|pmd)_mkdirty on VMAs without write permissions. If an architecture implementation is wrong, we might accidentally set the PTE/PMD writable and allow for write access in a VMA without write permissions. The tests include reproducers for the two issues recently discovered and worked-around in core-MM for now: (1) commit 624a2c94f5b7 ("Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"") (2) commit 96a9c287e25d ("mm/migrate: fix wrongly apply write bit after mkdirty on sparc64") In addition, some other tests that reveal further issues. All tests pass under x86_64: ./mkdirty # [INFO] detected THP size: 2048 KiB TAP version 13 1..6 # [INFO] PTRACE write access ok 1 SIGSEGV generated, page not modified # [INFO] PTRACE write access to THP ok 2 SIGSEGV generated, page not modified # [INFO] Page migration ok 3 SIGSEGV generated, page not modified # [INFO] Page migration of THP ok 4 SIGSEGV generated, page not modified # [INFO] PTE-mapping a THP ok 5 SIGSEGV generated, page not modified # [INFO] UFFDIO_COPY ok 6 SIGSEGV generated, page not modified # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0 But some fail on sparc64: ./mkdirty # [INFO] detected THP size: 8192 KiB TAP version 13 1..6 # [INFO] PTRACE write access not ok 1 SIGSEGV generated, page not modified # [INFO] PTRACE write access to THP not ok 2 SIGSEGV generated, page not modified # [INFO] Page migration ok 3 SIGSEGV generated, page not modified # [INFO] Page migration of THP ok 4 SIGSEGV generated, page not modified # [INFO] PTE-mapping a THP ok 5 SIGSEGV generated, page not modified # [INFO] UFFDIO_COPY not ok 6 SIGSEGV generated, page not modified Bail out! 3 out of 6 tests failed # Totals: pass:3 fail:3 xfail:0 xpass:0 skip:0 error:0 Reverting both above commits makes all tests fail on sparc64: ./mkdirty # [INFO] detected THP size: 8192 KiB TAP version 13 1..6 # [INFO] PTRACE write access not ok 1 SIGSEGV generated, page not modified # [INFO] PTRACE write access to THP not ok 2 SIGSEGV generated, page not modified # [INFO] Page migration not ok 3 SIGSEGV generated, page not modified # [INFO] Page migration of THP not ok 4 SIGSEGV generated, page not modified # [INFO] PTE-mapping a THP not ok 5 SIGSEGV generated, page not modified # [INFO] UFFDIO_COPY not ok 6 SIGSEGV generated, page not modified Bail out! 6 out of 6 tests failed # Totals: pass:0 fail:6 xfail:0 xpass:0 skip:0 error:0 The tests are useful to detect other problematic archs, to verify new arch fixes, and to stop such issues from reappearing in the future. For now, we don't add any hugetlb tests. Signed-off-by: David Hildenbrand --- tools/testing/selftests/mm/Makefile | 2 + tools/testing/selftests/mm/mkdirty.c | 379 +++++++++++++++++++++++++++ 2 files changed, 381 insertions(+) create mode 100644 tools/testing/selftests/mm/mkdirty.c diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile index c31d952cff68..8235dddbbbc6 100644 --- a/tools/testing/selftests/mm/Makefile +++ b/tools/testing/selftests/mm/Makefile @@ -47,6 +47,7 @@ TEST_GEN_FILES += map_hugetlb TEST_GEN_FILES += map_populate TEST_GEN_FILES += memfd_secret TEST_GEN_FILES += migration +TEST_GEN_PROGS += mkdirty TEST_GEN_FILES += mlock-random-test TEST_GEN_FILES += mlock2-tests TEST_GEN_FILES += mrelease_test @@ -108,6 +109,7 @@ $(OUTPUT)/cow: vm_util.c $(OUTPUT)/khugepaged: vm_util.c $(OUTPUT)/ksm_functional_tests: vm_util.c $(OUTPUT)/madv_populate: vm_util.c +$(OUTPUT)/mkdirty: vm_util.c $(OUTPUT)/soft-dirty: vm_util.c $(OUTPUT)/split_huge_page_test: vm_util.c $(OUTPUT)/userfaultfd: vm_util.c diff --git a/tools/testing/selftests/mm/mkdirty.c b/tools/testing/selftests/mm/mkdirty.c new file mode 100644 index 000000000000..6d71d972997b --- /dev/null +++ b/tools/testing/selftests/mm/mkdirty.c @@ -0,0 +1,379 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Test handling of code that might set PTE/PMD dirty in read-only VMAs. + * Setting a PTE/PMD dirty must not accidentally set the PTE/PMD writable. + * + * Copyright 2023, Red Hat, Inc. + * + * Author(s): David Hildenbrand + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest.h" +#include "vm_util.h" + +static size_t pagesize; +static size_t thpsize; +static int mem_fd; +static int pagemap_fd; +static sigjmp_buf env; + +static void signal_handler(int sig) +{ + if (sig == SIGSEGV) + siglongjmp(env, 1); + siglongjmp(env, 2); +} + +static void do_test_write_sigsegv(char *mem) +{ + char orig = *mem; + int ret; + + if (signal(SIGSEGV, signal_handler) == SIG_ERR) { + ksft_test_result_fail("signal() failed\n"); + return; + } + + ret = sigsetjmp(env, 1); + if (!ret) + *mem = orig + 1; + + if (signal(SIGSEGV, SIG_DFL) == SIG_ERR) + ksft_test_result_fail("signal() failed\n"); + + ksft_test_result(ret == 1 && *mem == orig, + "SIGSEGV generated, page not modified\n"); +} + +static char *mmap_thp_range(int prot, char **_mmap_mem, size_t *_mmap_size) +{ + const size_t mmap_size = 2 * thpsize; + char *mem, *mmap_mem; + + mmap_mem = mmap(NULL, mmap_size, prot, MAP_PRIVATE|MAP_ANON, + -1, 0); + if (mmap_mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return MAP_FAILED; + } + mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + + if (madvise(mem, thpsize, MADV_HUGEPAGE)) { + ksft_test_result_skip("MADV_HUGEPAGE failed\n"); + munmap(mmap_mem, mmap_size); + return MAP_FAILED; + } + + *_mmap_mem = mmap_mem; + *_mmap_size = mmap_size; + return mem; +} + +static void test_ptrace_write(void) +{ + char data = 1; + char *mem; + int ret; + + ksft_print_msg("[INFO] PTRACE write access\n"); + + mem = mmap(NULL, pagesize, PROT_READ, MAP_PRIVATE|MAP_ANON, -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + /* Fault in the shared zeropage. */ + if (*mem != 0) { + ksft_test_result_fail("Memory not zero\n"); + goto munmap; + } + + /* + * Unshare the page (populating a fresh anon page that might be set + * dirty in the PTE) in the read-only VMA using ptrace (FOLL_FORCE). + */ + lseek(mem_fd, (uintptr_t) mem, SEEK_SET); + ret = write(mem_fd, &data, 1); + if (ret != 1 || *mem != data) { + ksft_test_result_fail("write() failed\n"); + goto munmap; + } + + do_test_write_sigsegv(mem); +munmap: + munmap(mem, pagesize); +} + +static void test_ptrace_write_thp(void) +{ + char *mem, *mmap_mem; + size_t mmap_size; + char data = 1; + int ret; + + ksft_print_msg("[INFO] PTRACE write access to THP\n"); + + mem = mmap_thp_range(PROT_READ, &mmap_mem, &mmap_size); + if (mem == MAP_FAILED) + return; + + /* + * Write to the first subpage in the read-only VMA using + * ptrace(FOLL_FORCE), eventually placing a fresh THP that is marked + * dirty in the PMD. + */ + lseek(mem_fd, (uintptr_t) mem, SEEK_SET); + ret = write(mem_fd, &data, 1); + if (ret != 1 || *mem != data) { + ksft_test_result_fail("write() failed\n"); + goto munmap; + } + + /* MM populated a THP if we got the last subpage populated as well. */ + if (!pagemap_is_populated(pagemap_fd, mem + thpsize - pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + + do_test_write_sigsegv(mem); +munmap: + munmap(mmap_mem, mmap_size); +} + +static void test_page_migration(void) +{ + char *mem; + + ksft_print_msg("[INFO] Page migration\n"); + + mem = mmap(NULL, pagesize, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, + -1, 0); + if (mem == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + /* Populate a fresh page and dirty it. */ + memset(mem, 1, pagesize); + if (mprotect(mem, pagesize, PROT_READ)) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + + /* Trigger page migration. Might not be available or fail. */ + if (syscall(__NR_mbind, mem, pagesize, MPOL_LOCAL, NULL, 0x7fful, + MPOL_MF_MOVE)) { + ksft_test_result_skip("mbind() failed\n"); + goto munmap; + } + + do_test_write_sigsegv(mem); +munmap: + munmap(mem, pagesize); +} + +static void test_page_migration_thp(void) +{ + char *mem, *mmap_mem; + size_t mmap_size; + + ksft_print_msg("[INFO] Page migration of THP\n"); + + mem = mmap_thp_range(PROT_READ|PROT_WRITE, &mmap_mem, &mmap_size); + if (mem == MAP_FAILED) + return; + + /* + * Write to the first page, which might populate a fresh anon THP + * and dirty it. + */ + memset(mem, 1, pagesize); + if (mprotect(mem, thpsize, PROT_READ)) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + + /* MM populated a THP if we got the last subpage populated as well. */ + if (!pagemap_is_populated(pagemap_fd, mem + thpsize - pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + + /* Trigger page migration. Might not be available or fail. */ + if (syscall(__NR_mbind, mem, thpsize, MPOL_LOCAL, NULL, 0x7fful, + MPOL_MF_MOVE)) { + ksft_test_result_skip("mbind() failed\n"); + goto munmap; + } + + do_test_write_sigsegv(mem); +munmap: + munmap(mmap_mem, mmap_size); +} + +static void test_pte_mapped_thp(void) +{ + char *mem, *mmap_mem; + size_t mmap_size; + + ksft_print_msg("[INFO] PTE-mapping a THP\n"); + + mem = mmap_thp_range(PROT_READ|PROT_WRITE, &mmap_mem, &mmap_size); + if (mem == MAP_FAILED) + return; + + /* + * Write to the first page, which might populate a fresh anon THP + * and dirty it. + */ + memset(mem, 1, pagesize); + if (mprotect(mem, thpsize, PROT_READ)) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + + /* MM populated a THP if we got the last subpage populated as well. */ + if (!pagemap_is_populated(pagemap_fd, mem + thpsize - pagesize)) { + ksft_test_result_skip("Did not get a THP populated\n"); + goto munmap; + } + + /* Trigger PTE-mapping the THP by mprotect'ing the last subpage. */ + if (mprotect(mem + thpsize - pagesize, pagesize, + PROT_READ|PROT_WRITE)) { + ksft_test_result_fail("mprotect() failed\n"); + goto munmap; + } + + do_test_write_sigsegv(mem); +munmap: + munmap(mmap_mem, mmap_size); +} + +#ifdef __NR_userfaultfd +static void test_uffdio_copy(void) +{ + struct uffdio_register uffdio_register; + struct uffdio_copy uffdio_copy; + struct uffdio_api uffdio_api; + char *dst, *src; + int uffd; + + ksft_print_msg("[INFO] UFFDIO_COPY\n"); + + src = malloc(pagesize); + memset(src, 1, pagesize); + dst = mmap(NULL, pagesize, PROT_READ, MAP_PRIVATE|MAP_ANON, -1, 0); + if (dst == MAP_FAILED) { + ksft_test_result_fail("mmap() failed\n"); + return; + } + + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd < 0) { + ksft_test_result_skip("__NR_userfaultfd failed\n"); + goto munmap; + } + + uffdio_api.api = UFFD_API; + uffdio_api.features = 0; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) < 0) { + ksft_test_result_fail("UFFDIO_API failed\n"); + goto close_uffd; + } + + uffdio_register.range.start = (unsigned long) dst; + uffdio_register.range.len = pagesize; + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) { + ksft_test_result_fail("UFFDIO_REGISTER failed\n"); + goto close_uffd; + } + + /* Place a page in a read-only VMA, which might set the PTE dirty. */ + uffdio_copy.dst = (unsigned long) dst; + uffdio_copy.src = (unsigned long) src; + uffdio_copy.len = pagesize; + uffdio_copy.mode = 0; + if (ioctl(uffd, UFFDIO_COPY, &uffdio_copy)) { + ksft_test_result_fail("UFFDIO_COPY failed\n"); + goto close_uffd; + } + + do_test_write_sigsegv(dst); +close_uffd: + close(uffd); +munmap: + munmap(dst, pagesize); + free(src); +#endif /* __NR_userfaultfd */ +} + +int main(void) +{ + int err, tests = 2; + + pagesize = getpagesize(); + thpsize = read_pmd_pagesize(); + if (thpsize) { + ksft_print_msg("[INFO] detected THP size: %zu KiB\n", + thpsize / 1024); + tests += 3; + } +#ifdef __NR_userfaultfd + tests += 1; +#endif /* __NR_userfaultfd */ + + ksft_print_header(); + ksft_set_plan(tests); + + mem_fd = open("/proc/self/mem", O_RDWR); + if (mem_fd < 0) + ksft_exit_fail_msg("opening /proc/self/mem failed\n"); + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_msg("opening /proc/self/pagemap failed\n"); + + /* + * On some ptrace(FOLL_FORCE) write access via /proc/self/mem in + * read-only VMAs, the kernel may set the PTE/PMD dirty. + */ + test_ptrace_write(); + if (thpsize) + test_ptrace_write_thp(); + /* + * On page migration, the kernel may set the PTE/PMD dirty when + * remapping the page. + */ + test_page_migration(); + if (thpsize) + test_page_migration_thp(); + /* PTE-mapping a THP might propagate the dirty PMD bit to the PTEs. */ + if (thpsize) + test_pte_mapped_thp(); + /* Placing a fresh page via userfaultfd may set the PTE dirty. */ +#ifdef __NR_userfaultfd + test_uffdio_copy(); +#endif /* __NR_userfaultfd */ + + err = ksft_get_fail_cnt(); + if (err) + ksft_exit_fail_msg("%d out of %d tests failed\n", + err, ksft_test_num()); + return ksft_exit_pass(); +} From patchwork Tue Apr 11 14:15:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81993 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2615496vqo; Tue, 11 Apr 2023 07:24:18 -0700 (PDT) X-Google-Smtp-Source: AKy350bvt2y3w0zyAEc1QfFXrOdvWhgHmqqB+IcRK5pT29jg9B1+/jHd3rqdV6/kGDDtdAYVdJuJ X-Received: by 2002:a05:6a20:4e10:b0:c6:c0c1:b1fe with SMTP id gk16-20020a056a204e1000b000c6c0c1b1femr12385312pzb.57.1681223057753; Tue, 11 Apr 2023 07:24:17 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681223057; cv=none; d=google.com; s=arc-20160816; b=NZhUyuzPNQ9cJVW8ymvNWPPb2S9rvQCV4/vrotUW4PgCPLtg2Q1/z2WpZWzwWD4jeS Od3VQfS861mDWKKFiZ6KtOvQTTAbX2VcQwobqyVP3r86G3xVo+km1I4SyjfoW5/xlB6o qe/HLij4YIX2BRQOAZPlksrMrp1Z44xGyYAn7+FRUXGRXT86BMJgL5XdVLHtEI7lYRNX f6hAbDPtFzskDPGJ76bov/j83Bh+UoJDQiaTRk1k9wJK0dd4KT4kFSQQEFmjLs/COOD3 8gkB4RABGRwZOncHUrvkDHSkRvkXNkTlP5wLM/vRBhdJFV5zY8MwC1zY0/otfJUs0Tn6 MoZw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=VwTQ8oLmv6mJPSwow3w38v2InKFos9H0Yp4Ad7AU1D8=; b=eCkNV+iDIzQCYW3oj/KdVI9j99W2mUBDZsEApLmXEVqKXAWml8aoTW0SSTJzJkSdRj nIUpqcdRT9zTpalchCbUYk5LWWWoIIuy7XFrU/3X8XU7b9kpw5YgrEeXZPSliOzXBfHh sEhj10/Jl5kdb1awMyaHxwsk80aW3bSHjZAWpxmhuTgiQl94iF0jEuoxyusDImusBRoi YD9icMQdCL8AQjsBAKxD/nOw7d4G6FeevPnjaFDcp8sR3Eb2s4dZ3yH5u/Bgw/s1Uivu kqZfcsvlv/MKEn3sh6l19HLeL+A9Qo909q5PtSMFZPXFaRQ3lZQmTNylbmhq8+QTwyuS xNsg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=b2bpNsez; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id q8-20020a635c08000000b0050bf22172d3si13332663pgb.490.2023.04.11.07.23.35; Tue, 11 Apr 2023 07:24:17 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=b2bpNsez; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230224AbjDKORn (ORCPT + 99 others); Tue, 11 Apr 2023 10:17:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229939AbjDKORV (ORCPT ); Tue, 11 Apr 2023 10:17:21 -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 16FAF49ED for ; Tue, 11 Apr 2023 07:15:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222550; 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: in-reply-to:in-reply-to:references:references; bh=VwTQ8oLmv6mJPSwow3w38v2InKFos9H0Yp4Ad7AU1D8=; b=b2bpNsezngzTj0GhvSSgy4c5tzmvfsViE3ovH5434JfdOjWKYq7CXHtKdqvPNd+IdPf0w+ tW08xQ2+qAP9rdS8X1U0kXoxpJbvuvQ/BJ0xnT+b4mNuyW9rNO+XU0mzTS7jgiSx0ak47e 2DxrgZY3OTfkiVzQWqsiYa5GGmKkKYk= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-192-6m8W4uXYOJij1C-eHrqkJw-1; Tue, 11 Apr 2023 10:15:47 -0400 X-MC-Unique: 6m8W4uXYOJij1C-eHrqkJw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CFB748996F4; Tue, 11 Apr 2023 14:15:40 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id ABE2F400F285; Tue, 11 Apr 2023 14:15:39 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 3/6] sparc/mm: don't unconditionally set HW writable bit when setting PTE dirty on 64bit Date: Tue, 11 Apr 2023 16:15:26 +0200 Message-Id: <20230411141529.428991-5-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890148935281444?= X-GMAIL-MSGID: =?utf-8?q?1762890148935281444?= On sparc64, there is no HW modified bit, therefore, SW tracks via a SW bit if the PTE is dirty via pte_mkdirty(). However, pte_mkdirty() currently also unconditionally sets the HW writable bit, which is wrong. pte_mkdirty() is not supposed to make a PTE actually writable, unless the SW writable bit -- pte_write() -- indicates that the PTE is not write-protected. Fortunately, sparc64 also defines a SW writable bit. For example, this already turned into a problem in the context of THP splitting as documented in commit 624a2c94f5b7 ("Partly revert "mm/thp: carry over dirty bit when thp splits on pmd""), and for page migration, as documented in commit 96a9c287e25d ("mm/migrate: fix wrongly apply write bit after mkdirty on sparc64"). Also, we might want to use the dirty PTE bit in the context of KSM with shared zeropage [1], whereby setting the page writable would be problematic. But more general, any code that might end up setting a PTE/PMD dirty inside a VM without write permissions is possibly broken, Before this commit (sun4u in QEMU): root@debian:~/linux/tools/testing/selftests/mm# ./mkdirty # [INFO] detected THP size: 8192 KiB TAP version 13 1..6 # [INFO] PTRACE write access not ok 1 SIGSEGV generated, page not modified # [INFO] PTRACE write access to THP not ok 2 SIGSEGV generated, page not modified # [INFO] Page migration ok 3 SIGSEGV generated, page not modified # [INFO] Page migration of THP ok 4 SIGSEGV generated, page not modified # [INFO] PTE-mapping a THP ok 5 SIGSEGV generated, page not modified # [INFO] UFFDIO_COPY not ok 6 SIGSEGV generated, page not modified Bail out! 3 out of 6 tests failed # Totals: pass:3 fail:3 xfail:0 xpass:0 skip:0 error:0 Test #3,#4,#5 pass ever since we added some MM workarounds, the underlying issue remains. Let's fix the remaining issues and prepare for reverting the workarounds by setting the HW writable bit only if both, the SW dirty bit and the SW writable bit are set. We have to move pte_dirty() and pte_dirty() up. The code patching mechanism and handling constants > 22bit is a bit special on sparc64. The ASM logic in pte_mkdirty() and pte_mkwrite() match the logic in pte_mkold() to create the mask depending on the machine type. The ASM logic in __pte_mkhwwrite() matches the logic in pte_present(), just using an "or" instead of an "and" instruction. With this commit (sun4u in QEMU): root@debian:~/linux/tools/testing/selftests/mm# ./mkdirty # [INFO] detected THP size: 8192 KiB TAP version 13 1..6 # [INFO] PTRACE write access ok 1 SIGSEGV generated, page not modified # [INFO] PTRACE write access to THP ok 2 SIGSEGV generated, page not modified # [INFO] Page migration ok 3 SIGSEGV generated, page not modified # [INFO] Page migration of THP ok 4 SIGSEGV generated, page not modified # [INFO] PTE-mapping a THP ok 5 SIGSEGV generated, page not modified # [INFO] UFFDIO_COPY ok 6 SIGSEGV generated, page not modified # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0 This handling seems to have been in place forever. [1] https://lkml.kernel.org/r/533a7c3d-3a48-b16b-b421-6e8386e0b142@redhat.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: David Hildenbrand --- arch/sparc/include/asm/pgtable_64.h | 116 ++++++++++++++++------------ 1 file changed, 66 insertions(+), 50 deletions(-) diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h index 2dc8d4641734..5563efa1a19f 100644 --- a/arch/sparc/include/asm/pgtable_64.h +++ b/arch/sparc/include/asm/pgtable_64.h @@ -357,6 +357,42 @@ static inline pgprot_t pgprot_noncached(pgprot_t prot) */ #define pgprot_noncached pgprot_noncached +static inline unsigned long pte_dirty(pte_t pte) +{ + unsigned long mask; + + __asm__ __volatile__( + "\n661: mov %1, %0\n" + " nop\n" + " .section .sun4v_2insn_patch, \"ax\"\n" + " .word 661b\n" + " sethi %%uhi(%2), %0\n" + " sllx %0, 32, %0\n" + " .previous\n" + : "=r" (mask) + : "i" (_PAGE_MODIFIED_4U), "i" (_PAGE_MODIFIED_4V)); + + return (pte_val(pte) & mask); +} + +static inline unsigned long pte_write(pte_t pte) +{ + unsigned long mask; + + __asm__ __volatile__( + "\n661: mov %1, %0\n" + " nop\n" + " .section .sun4v_2insn_patch, \"ax\"\n" + " .word 661b\n" + " sethi %%uhi(%2), %0\n" + " sllx %0, 32, %0\n" + " .previous\n" + : "=r" (mask) + : "i" (_PAGE_WRITE_4U), "i" (_PAGE_WRITE_4V)); + + return (pte_val(pte) & mask); +} + #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags); #define arch_make_huge_pte arch_make_huge_pte @@ -418,28 +454,43 @@ static inline bool is_hugetlb_pte(pte_t pte) } #endif +static inline pte_t __pte_mkhwwrite(pte_t pte) +{ + unsigned long val = pte_val(pte); + + /* + * Note: we only want to set the HW writable bit if the SW writable bit + * and the SW dirty bit are set. + */ + __asm__ __volatile__( + "\n661: or %0, %2, %0\n" + " .section .sun4v_1insn_patch, \"ax\"\n" + " .word 661b\n" + " or %0, %3, %0\n" + " .previous\n" + : "=r" (val) + : "0" (val), "i" (_PAGE_W_4U), "i" (_PAGE_W_4V)); + + return __pte(val); +} + static inline pte_t pte_mkdirty(pte_t pte) { - unsigned long val = pte_val(pte), tmp; + unsigned long val = pte_val(pte), mask; __asm__ __volatile__( - "\n661: or %0, %3, %0\n" - " nop\n" - "\n662: nop\n" + "\n661: mov %1, %0\n" " nop\n" " .section .sun4v_2insn_patch, \"ax\"\n" " .word 661b\n" - " sethi %%uhi(%4), %1\n" - " sllx %1, 32, %1\n" - " .word 662b\n" - " or %1, %%lo(%4), %1\n" - " or %0, %1, %0\n" + " sethi %%uhi(%2), %0\n" + " sllx %0, 32, %0\n" " .previous\n" - : "=r" (val), "=r" (tmp) - : "0" (val), "i" (_PAGE_MODIFIED_4U | _PAGE_W_4U), - "i" (_PAGE_MODIFIED_4V | _PAGE_W_4V)); + : "=r" (mask) + : "i" (_PAGE_MODIFIED_4U), "i" (_PAGE_MODIFIED_4V)); - return __pte(val); + pte = __pte(val | mask); + return pte_write(pte) ? __pte_mkhwwrite(pte) : pte; } static inline pte_t pte_mkclean(pte_t pte) @@ -481,7 +532,8 @@ static inline pte_t pte_mkwrite(pte_t pte) : "=r" (mask) : "i" (_PAGE_WRITE_4U), "i" (_PAGE_WRITE_4V)); - return __pte(val | mask); + pte = __pte(val | mask); + return pte_dirty(pte) ? __pte_mkhwwrite(pte) : pte; } static inline pte_t pte_wrprotect(pte_t pte) @@ -584,42 +636,6 @@ static inline unsigned long pte_young(pte_t pte) return (pte_val(pte) & mask); } -static inline unsigned long pte_dirty(pte_t pte) -{ - unsigned long mask; - - __asm__ __volatile__( - "\n661: mov %1, %0\n" - " nop\n" - " .section .sun4v_2insn_patch, \"ax\"\n" - " .word 661b\n" - " sethi %%uhi(%2), %0\n" - " sllx %0, 32, %0\n" - " .previous\n" - : "=r" (mask) - : "i" (_PAGE_MODIFIED_4U), "i" (_PAGE_MODIFIED_4V)); - - return (pte_val(pte) & mask); -} - -static inline unsigned long pte_write(pte_t pte) -{ - unsigned long mask; - - __asm__ __volatile__( - "\n661: mov %1, %0\n" - " nop\n" - " .section .sun4v_2insn_patch, \"ax\"\n" - " .word 661b\n" - " sethi %%uhi(%2), %0\n" - " sllx %0, 32, %0\n" - " .previous\n" - : "=r" (mask) - : "i" (_PAGE_WRITE_4U), "i" (_PAGE_WRITE_4V)); - - return (pte_val(pte) & mask); -} - static inline unsigned long pte_exec(pte_t pte) { unsigned long mask; From patchwork Tue Apr 11 14:15:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81999 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2619080vqo; Tue, 11 Apr 2023 07:29:48 -0700 (PDT) X-Google-Smtp-Source: AKy350ZZVfrj4gVJvFx7TCM3LsV+haWFWVFag9JKsWHVDsvO+qfQzmSkZYDS5YVz/25IE3SV0R5c X-Received: by 2002:a17:902:e30c:b0:19c:65bd:d44b with SMTP id q12-20020a170902e30c00b0019c65bdd44bmr11189576plc.60.1681223388503; Tue, 11 Apr 2023 07:29:48 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681223388; cv=none; d=google.com; s=arc-20160816; b=MYEPDjVJYzov8Y7LsFfOBvwfak2gMdcpT/i5LyG674jOJTCzTAIbPRcq4iNwoDXwFz HXLH2n6mcxL9woJrdCO9Ps4agvcN5KMswof0/u6edp+G1ClNpz5WFzdXZ8nuisymV7sl N5M+vQa60Fvge6AeRClzMGM20FrcxFnCrCZmqM6Q0dsYxB75V0hZ269DwcEuK/rB2V3n O6hEPdSc4kT8h8R4eKdlX8IqIbwIGG3RaWOje3f2EwITbCKI6yMoJTTqo3DVdjeIaZyt N31EH477sBtA5YiLe1KIvXR0By+Uz0DCXm/fPIWyoMBWG3KMPS4nhHpCFLQiDXtRztzw fngQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=TCmOrD6a+wU+gQBMdrpGdoWY5w1T2pXs/1sAiD9BNP4=; b=tGAcoT458lj8xziQsPsDeKz+o+vGh1YK1o3yE20KcEwxNxFiuXyMVD7Dyf2UXzvAfR Bf2tPRuYjllpX46H6xymi3dOyauv7DCm57v11R3JhNfwH0ykfvDoSaYFiZB/6VoufazW yI7sHYP6hPDUwIJrNZq1KNZ5S8hv/9Gc95Y8NTVuW9YypdJAwLbUjEK7nw7JSXeEgD4N HRHWiT4a6KvG8nMy+WdO+IPRgmgTnKX86WnfxEJjaWDRk/iN9xQGnFr437cN/7ZzzJ0u LGGyC++jlooZziu1NdLKmuwW0gTt7PGDkXvqJuN8+qJNzsIf+wylnroEf7626t42Q+RP DSnw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=bcu5wu8A; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id 66-20020a630145000000b005077dda0477si13844618pgb.802.2023.04.11.07.29.35; Tue, 11 Apr 2023 07:29:48 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=bcu5wu8A; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229886AbjDKOQd (ORCPT + 99 others); Tue, 11 Apr 2023 10:16:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229545AbjDKOQa (ORCPT ); Tue, 11 Apr 2023 10:16:30 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0474EE4C for ; Tue, 11 Apr 2023 07:15:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222544; 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: in-reply-to:in-reply-to:references:references; bh=TCmOrD6a+wU+gQBMdrpGdoWY5w1T2pXs/1sAiD9BNP4=; b=bcu5wu8AydCIPl15MQcOjNEIRouoLljOLn/4k4kR/9XRWYg4Qt1L5GxXs0pl/przKwAAwg 5iJBxVEhXsBal03QqSJ1c2+WWX6A8csBqg7PQnnQ7xn6oakk8XHHbzIlVKRNjV/1MdEum2 qwlBPJ/lrM/Y9sl0JVVNhWh2HbLFfnw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-197-8t3asOMrN_Sxm6SwwHsM4A-1; Tue, 11 Apr 2023 10:15:42 -0400 X-MC-Unique: 8t3asOMrN_Sxm6SwwHsM4A-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 14C95185A791; Tue, 11 Apr 2023 14:15:42 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 16E57400F285; Tue, 11 Apr 2023 14:15:40 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 4/6] mm/migrate: revert "mm/migrate: fix wrongly apply write bit after mkdirty on sparc64" Date: Tue, 11 Apr 2023 16:15:27 +0200 Message-Id: <20230411141529.428991-6-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890495962908213?= X-GMAIL-MSGID: =?utf-8?q?1762890495962908213?= This reverts commit 96a9c287e25d ("mm/migrate: fix wrongly apply write bit after mkdirty on sparc64"). Now that sparc64 mkdirty handling is fixed and no longer sets a PTE/PMD writable that shouldn't be writable, let's revert the temporary fix. The mkdirty mm selftest still passes with this change on sparc64. Note that loongarch handling was fixed in commit bf2f34a506e6 ("LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()"). Signed-off-by: David Hildenbrand --- mm/huge_memory.c | 6 ++---- mm/migrate.c | 2 -- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 032fb0ef9cd1..ec86bf1d4e81 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3276,6 +3276,8 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) pmde = mk_huge_pmd(new, READ_ONCE(vma->vm_page_prot)); if (pmd_swp_soft_dirty(*pvmw->pmd)) pmde = pmd_mksoft_dirty(pmde); + if (is_writable_migration_entry(entry)) + pmde = maybe_pmd_mkwrite(pmde, vma); if (pmd_swp_uffd_wp(*pvmw->pmd)) pmde = pmd_mkuffd_wp(pmde); if (!is_migration_entry_young(entry)) @@ -3283,10 +3285,6 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) /* NOTE: this may contain setting soft-dirty on some archs */ if (PageDirty(new) && is_migration_entry_dirty(entry)) pmde = pmd_mkdirty(pmde); - if (is_writable_migration_entry(entry)) - pmde = maybe_pmd_mkwrite(pmde, vma); - else - pmde = pmd_wrprotect(pmde); if (PageAnon(new)) { rmap_t rmap_flags = RMAP_COMPOUND; diff --git a/mm/migrate.c b/mm/migrate.c index db3f154446af..3b21c44e2176 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -225,8 +225,6 @@ static bool remove_migration_pte(struct folio *folio, pte = maybe_mkwrite(pte, vma); else if (pte_swp_uffd_wp(*pvmw.pte)) pte = pte_mkuffd_wp(pte); - else - pte = pte_wrprotect(pte); if (folio_test_anon(folio) && !is_readable_migration_entry(entry)) rmap_flags |= RMAP_EXCLUSIVE; From patchwork Tue Apr 11 14:15:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81998 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2618220vqo; Tue, 11 Apr 2023 07:28:31 -0700 (PDT) X-Google-Smtp-Source: AKy350aNgCF8nioTW42sNXMaGNmMXBrfckCGI5uZaifYO/rymZYIaMGndGexvYGpgyZpevH1jfmb X-Received: by 2002:a62:170c:0:b0:625:13f3:9409 with SMTP id 12-20020a62170c000000b0062513f39409mr16341019pfx.26.1681223310964; Tue, 11 Apr 2023 07:28:30 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681223310; cv=none; d=google.com; s=arc-20160816; b=fFBp92YblFq516ojSUEfygeLb5Au+gMCUdf9tnLd4kT031bbWG+nvuRPN1WzQGyScH r5VRpPFCGzQe2VdNTmDbxRTwfZcZ5gBjDVfgXiLys10dkLpdAQeNYJQA/+ev3YaySwLx jlXSSjcRSYwL1ezYbChX6cCQwaaJxHhW8yF7VayQa0NtgfVJFraCEE/obw/LgbY6xyxg 5gfO7cPxWGqtKtaNEJbrJZqvVupv4fEvIWdArcktUZTfZGq4ed3Bx1mGv9E+Ydujfb3b rmb1iHZN0q00aGY08ykHlxDAjO2SRT6dQKoBvdj9OalRtNBp5cCTK+0C6CZ+nVXodFth gFTQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=kMuXjs2koZ/Flt7PJQx7eiW1x5ktANLpUol8YMKeKVs=; b=cN29j8EpOEWjR+NHRju09ves1YJsXnEdTzpxdEZhpp5/tf9B5gtseERO2mgsyDZdb9 ayTPv6skFXu/QCwB8redQM+vssRtaYSK9ZcSyrmI036Ivr3H2yImNjWrC5rrAzQz3a4+ UXnyE6l2chONsyVJzAyxGnDFATBHRW+MPca4RVTquxEv1YMIZowxS+U6huLdHoYJNryt t+cERQbkqO0V3LAX8G0++Zwu7FJVxnRySc7jaHZxUhHEwVfMedyzlmSAzJKahNzGisnw ZHlEGu/nGIzWxaeYKsQrhfiTKKBvUwGde1l8coa6dnSva0bk9AvbPw9ecnKq52d0ppPc N30w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=fhr4l54Z; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id h30-20020a056a00001e00b006259cf8a646si7147408pfk.43.2023.04.11.07.28.18; Tue, 11 Apr 2023 07:28:30 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=fhr4l54Z; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230221AbjDKORX (ORCPT + 99 others); Tue, 11 Apr 2023 10:17:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229995AbjDKORP (ORCPT ); Tue, 11 Apr 2023 10:17:15 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C545F3A91 for ; Tue, 11 Apr 2023 07:15:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222547; 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: in-reply-to:in-reply-to:references:references; bh=kMuXjs2koZ/Flt7PJQx7eiW1x5ktANLpUol8YMKeKVs=; b=fhr4l54Zra7EkLgbgjjHIiTDbm1Ig0wm0mOnUUf3/m246ZCfYQJtDYL2GAKj+NzbJSpc9y WfR4f8cVo/Z8K7eHAdckI8RbaxHk4s6PRY/hetKJ3DkVsTPmRWoloe93eGUTgZpSf4LsyD KM2+ZUd3a9ydoWeE/x/FsEzo4CNTbCE= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [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-665-zLozqPi3M5SQg6bnZDFiDQ-1; Tue, 11 Apr 2023 10:15:44 -0400 X-MC-Unique: zLozqPi3M5SQg6bnZDFiDQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4008E1C0A5A5; Tue, 11 Apr 2023 14:15:43 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4E630400F287; Tue, 11 Apr 2023 14:15:42 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 5/6] mm/huge_memory: revert "Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"" Date: Tue, 11 Apr 2023 16:15:28 +0200 Message-Id: <20230411141529.428991-7-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890414405771305?= X-GMAIL-MSGID: =?utf-8?q?1762890414405771305?= This reverts commit 624a2c94f5b7 ("Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"") and the fixup in commit e833bc503405 ("mm/thp: re-apply mkdirty for small pages after split"). Now that sparc64 mkdirty handling is fixed and no longer sets a PTE/PMD writable that shouldn't be writable, let's revert the temporary fix and remove the stale comment. The mkdirty mm selftest still passes with this change on sparc64. Note that loongarch handling was fixed in commit bf2f34a506e6 ("LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()") Signed-off-by: David Hildenbrand --- mm/huge_memory.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ec86bf1d4e81..6f3af65435c8 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2238,18 +2238,13 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = maybe_mkwrite(entry, vma); if (anon_exclusive) SetPageAnonExclusive(page + i); + if (!write) + entry = pte_wrprotect(entry); if (!young) entry = pte_mkold(entry); /* NOTE: this may set soft-dirty too on some archs */ if (dirty) entry = pte_mkdirty(entry); - /* - * NOTE: this needs to happen after pte_mkdirty, - * because some archs (sparc64, loongarch) could - * set hw write bit when mkdirty. - */ - if (!write) - entry = pte_wrprotect(entry); if (soft_dirty) entry = pte_mksoft_dirty(entry); if (uffd_wp) From patchwork Tue Apr 11 14:15:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 81996 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2617362vqo; Tue, 11 Apr 2023 07:27:10 -0700 (PDT) X-Google-Smtp-Source: AKy350bwDoRSfmf6DXZnhrwcTjW+ZB4vizPWQpFtVcTaNqX2V6zOsaz5WYcrYoEFYyCQ+IHNoxt1 X-Received: by 2002:a17:903:2886:b0:1a6:413c:4a47 with SMTP id ku6-20020a170903288600b001a6413c4a47mr6381384plb.1.1681223230533; Tue, 11 Apr 2023 07:27:10 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681223230; cv=none; d=google.com; s=arc-20160816; b=P5hbLwnq3ynVMcZFKc2vESUtBybpnwsZaTNUBjNVGz8mogk5o+6HHcPrMe5SWerbvJ ZuNJ5YHHFF0+ABSpv8cG4lGU8dOJBOYOQ4ChaWq+J6BuMIRsKW2jRdli7KBEG3WicLS6 thOmKAS2L7twQ+l/T1A9YhXlSHfmNCVBQaqizZf1L4dbswqgB+8JNJYOuD3WYyrryG04 Py1mMw8q7Zk1iW0K+VZbbGR3mr8yzg4vbZ4r3mAYU1lnCJnAA3d04Zry7+LRk0jkzu6w bboegF/Q+fBZsT08X1VkUi0J9v1V8+LSesiIjHiUdFQhiWa1m3+xbhjd6crCVWSor4x+ TXrA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=qzK4ogixuaREht4MpkiqqhFPvzGg6ALQmBRRBO9bEhw=; b=hB+priht4/SIzXYM6eN6LaB2M/f2bU0NmppHSL1HSycrv+QdSHuNDwz/awVMyAX4+q vaj6KmKyH4T6yeJDK0d7WtYbon4Rdk5z/nL9hynPxSV7PIgamLBMe5eemxDNPXVU7ofL lf4wLu1O4dM2Km9WyIOEfkKdyl3bkc39qE6g+pPczqCzaVb+rI67WRzmjYjzfROkimcG ZCsPc7CDE1NuGR2Y7wRX/BgbnLXirHXVNndA7ar8KrJ4hBoTBXcU5Toknq9kh6ivzwwK IRgOU+9ReOwyLK0vCAl9K7Bh022AAt/oi3l9EfN0se2tky/11Eo46qFupPXGgMGUS+wZ /1eA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=GNpxJ+7s; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id jy14-20020a17090342ce00b001a652580118si2717875plb.237.2023.04.11.07.26.57; Tue, 11 Apr 2023 07:27:10 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=GNpxJ+7s; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229988AbjDKORS (ORCPT + 99 others); Tue, 11 Apr 2023 10:17:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229944AbjDKORO (ORCPT ); Tue, 11 Apr 2023 10:17:14 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62559448B for ; Tue, 11 Apr 2023 07:15:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681222548; 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: in-reply-to:in-reply-to:references:references; bh=qzK4ogixuaREht4MpkiqqhFPvzGg6ALQmBRRBO9bEhw=; b=GNpxJ+7sI+jah3+/zAazYlQF38DN2IdKKwkWtN2oqqgUC42+irTJMuWA8pJUMNki9bOOL/ Dh5MWZvkaeCr1jYVczDlu9RiwrV/eKLYju+IuK7bovig4v4WbpGrDyCk27iGf/FKQZrRGY NqsRbuH5K/M6t7SI50irXJvOJ4Y3Efg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [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-371-Ckkwz92eO7-IkeIGQlURJg-1; Tue, 11 Apr 2023 10:15:45 -0400 X-MC-Unique: Ckkwz92eO7-IkeIGQlURJg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 17DDE1C12991; Tue, 11 Apr 2023 14:15:45 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9240D400F281; Tue, 11 Apr 2023 14:15:43 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, David Hildenbrand Subject: [PATCH v1 6/6] mm/huge_memory: conditionally call maybe_mkwrite() and drop pte_wrprotect() in __split_huge_pmd_locked() Date: Tue, 11 Apr 2023 16:15:29 +0200 Message-Id: <20230411141529.428991-8-david@redhat.com> In-Reply-To: <20230411141529.428991-1-david@redhat.com> References: <20230411141529.428991-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1762890306847760586?= X-GMAIL-MSGID: =?utf-8?q?1762890330285173466?= No need to call maybe_mkwrite() to then wrprotect if the source PMD was not writable. It's worth nothing that this now allows for PTEs to be writable even if the source PMD was not writable: if vma->vm_page_prot includes write permissions. As documented in commit 931298e103c2 ("mm/userfaultfd: rely on vma->vm_page_prot in uffd_wp_range()"), any mechanism that intends to have pages wrprotected (COW, writenotify, mprotect, uffd-wp, softdirty, ...) has to properly adjust vma->vm_page_prot upfront, to not include write permissions. If vma->vm_page_prot includes write permissions, the PTE/PMD can be writable as default. This now mimics the handling in mm/migrate.c:remove_migration_pte() and in mm/huge_memory.c:remove_migration_pmd(), which has been in place for a long time (except that 96a9c287e25d ("mm/migrate: fix wrongly apply write bit after mkdirty on sparc64") temporarily changed it). Signed-off-by: David Hildenbrand --- mm/huge_memory.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 6f3af65435c8..8332e16ac97b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2235,11 +2235,10 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = pte_swp_mkuffd_wp(entry); } else { entry = mk_pte(page + i, READ_ONCE(vma->vm_page_prot)); - entry = maybe_mkwrite(entry, vma); + if (write) + entry = maybe_mkwrite(entry, vma); if (anon_exclusive) SetPageAnonExclusive(page + i); - if (!write) - entry = pte_wrprotect(entry); if (!young) entry = pte_mkold(entry); /* NOTE: this may set soft-dirty too on some archs */