From patchwork Tue Aug 22 01:54:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360065 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 08740EE49AB for ; Tue, 22 Aug 2023 01:55:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232164AbjHVBzY (ORCPT ); Mon, 21 Aug 2023 21:55:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58918 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231974AbjHVBzX (ORCPT ); Mon, 21 Aug 2023 21:55:23 -0400 Received: from mail-il1-x132.google.com (mail-il1-x132.google.com [IPv6:2607:f8b0:4864:20::132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B155D180 for ; Mon, 21 Aug 2023 18:55:21 -0700 (PDT) Received: by mail-il1-x132.google.com with SMTP id e9e14a558f8ab-34ca2fcdf9fso6954145ab.0 for ; Mon, 21 Aug 2023 18:55:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669321; x=1693274121; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CsH3vkDr9agJVI3SouFCcK5RkzBRN3iHA9ib5+au0Rw=; b=CzldOLSR/1CFch60cKxnxJV7KC0TbczE/AS7NU3vcELLGEqTO96428h5zAJIQx9q47 qJfdzOYkvoVEnJLl8uynvnnrnlYgm5gqjmtv+3cgEgtH/Nt4FRLdULpgo/k3RjIb+SnU WTKw5yuYuGQnOEhCHelds3JU0dgsb9m7n0OS8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669321; x=1693274121; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CsH3vkDr9agJVI3SouFCcK5RkzBRN3iHA9ib5+au0Rw=; b=EwgqDAhHyO6uPPSJtpyMpImdCRVd+fuVBn4/w7Iaw/8w+ZbRHV1v+I1z0iP1Mdds5m 6dLb2JLyjsdK4+bCJ9jLyVdwQ1fg4zlnj/Pw957Z2SycCJG4Oth70Lm+J5k8BU67/duH z0rjZm1kr8Ddq8CCfPNZ3soocTjX6M8+DaqBUO4CReAEC9m8QHqUqhCEERAGpPrGiP6f KzVK50UMCZ0pzl1552fsPBgVUI2GfEE7+TaFwL8YJqzKhVBS56vpL+MfSEkfVVq9yJGA 6KoMdy83N3GAgfQeBHeph3puCZZZKaG6TCOJeIH1iGBdBD8h5OSWvNJin4oONgKiO0xV 3hMg== X-Gm-Message-State: AOJu0Yy0KTQVWgbAufEa9q64hn2790deYJeErk4wNfvEDPgFBjjFwnij 6LbnpJIcMW5FnPxtFDI7tnPm8A== X-Google-Smtp-Source: AGHT+IFjdGA7XRGfiXyy54FM+yhexl4gbxKokE/+1QN35KTpxnmuosD5M/koT6P5pAtsasmz/S2vng== X-Received: by 2002:a05:6e02:dce:b0:349:9938:a9b3 with SMTP id l14-20020a056e020dce00b003499938a9b3mr9158834ilj.3.1692669321018; Mon, 21 Aug 2023 18:55:21 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:20 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , Linus Torvalds , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 1/7] mm/mremap: Optimize the start addresses in move_page_tables() Date: Tue, 22 Aug 2023 01:54:54 +0000 Message-ID: <20230822015501.791637-2-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Recently, we see reports [1] of a warning that triggers due to move_page_tables() doing a downward and overlapping move on a mutually-aligned offset within a PMD. By mutual alignment, I mean the source and destination addresses of the mremap are at the same offset within a PMD. This mutual alignment along with the fact that the move is downward is sufficient to cause a warning related to having an allocated PMD that does not have PTEs in it. This warning will only trigger when there is mutual alignment in the move operation. A solution, as suggested by Linus Torvalds [2], is to initiate the copy process at the PMD level whenever such alignment is present. Implementing this approach will not only prevent the warning from being triggered, but it will also optimize the operation as this method should enhance the speed of the copy process whenever there's a possibility to start copying at the PMD level. Some more points: a. The optimization can be done only when both the source and destination of the mremap do not have anything mapped below it up to a PMD boundary. I add support to detect that. b. #1 is not a problem for the call to move_page_tables() from exec.c as nothing is expected to be mapped below the source. However, for non-overlapping mutually aligned moves as triggered by mremap(2), I added support for checking such cases. c. I currently only optimize for PMD moves, in the future I/we can build on this work and do PUD moves as well if there is a need for this. But I want to take it one step at a time. d. We need to be careful about mremap of ranges within the VMA itself. For this purpose, I added checks to determine if the address after alignment falls within its VMA itself. [1] https://lore.kernel.org/all/ZB2GTBD%2FLWTrkOiO@dhcp22.suse.cz/ [2] https://lore.kernel.org/all/CAHk-=whd7msp8reJPfeGNyt0LiySMT0egExx3TVZSX3Ok6X=9g@mail.gmail.com/ Suggested-by: Linus Torvalds Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- mm/mremap.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/mm/mremap.c b/mm/mremap.c index 11e06e4ab33b..035fbf542a8f 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -489,6 +489,53 @@ static bool move_pgt_entry(enum pgt_entry entry, struct vm_area_struct *vma, return moved; } +/* + * A helper to check if a previous mapping exists. Required for + * move_page_tables() and realign_addr() to determine if a previous mapping + * exists before we can do realignment optimizations. + */ +static bool can_align_down(struct vm_area_struct *vma, unsigned long addr_to_align, + unsigned long mask) +{ + unsigned long addr_masked = addr_to_align & mask; + + /* + * If @addr_to_align of either source or destination is not the beginning + * of the corresponding VMA, we can't align down or we will destroy part + * of the current mapping. + */ + if (vma->vm_start != addr_to_align) + return false; + + /* + * Make sure the realignment doesn't cause the address to fall on an + * existing mapping. + */ + return find_vma_intersection(vma->vm_mm, addr_masked, addr_to_align) == NULL; +} + +/* Opportunistically realign to specified boundary for faster copy. */ +static void try_realign_addr(unsigned long *old_addr, struct vm_area_struct *old_vma, + unsigned long *new_addr, struct vm_area_struct *new_vma, + unsigned long mask) +{ + /* Skip if the addresses are already aligned. */ + if ((*old_addr & ~mask) == 0) + return; + + /* Only realign if the new and old addresses are mutually aligned. */ + if ((*old_addr & ~mask) != (*new_addr & ~mask)) + return; + + /* Ensure realignment doesn't cause overlap with existing mappings. */ + if (!can_align_down(old_vma, *old_addr, mask) || + !can_align_down(new_vma, *new_addr, mask)) + return; + + *old_addr = *old_addr & mask; + *new_addr = *new_addr & mask; +} + unsigned long move_page_tables(struct vm_area_struct *vma, unsigned long old_addr, struct vm_area_struct *new_vma, unsigned long new_addr, unsigned long len, @@ -508,6 +555,14 @@ unsigned long move_page_tables(struct vm_area_struct *vma, return move_hugetlb_page_tables(vma, new_vma, old_addr, new_addr, len); + /* + * If possible, realign addresses to PMD boundary for faster copy. + * Only realign if the mremap copying hits a PMD boundary. + */ + if ((vma != new_vma) + && (len >= PMD_SIZE - (old_addr & ~PMD_MASK))) + try_realign_addr(&old_addr, vma, &new_addr, new_vma, PMD_MASK); + flush_cache_range(vma, old_addr, old_end); mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma->vm_mm, old_addr, old_end); @@ -577,6 +632,13 @@ unsigned long move_page_tables(struct vm_area_struct *vma, mmu_notifier_invalidate_range_end(&range); + /* + * Prevent negative return values when {old,new}_addr was realigned + * but we broke out of the above loop for the first PMD itself. + */ + if (len + old_addr < old_end) + return 0; + return len + old_addr - old_end; /* how much done */ } From patchwork Tue Aug 22 01:54:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360066 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 42767EE49AF for ; Tue, 22 Aug 2023 01:55:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232169AbjHVBzZ (ORCPT ); Mon, 21 Aug 2023 21:55:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231974AbjHVBzY (ORCPT ); Mon, 21 Aug 2023 21:55:24 -0400 Received: from mail-il1-x136.google.com (mail-il1-x136.google.com [IPv6:2607:f8b0:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8341113 for ; Mon, 21 Aug 2023 18:55:22 -0700 (PDT) Received: by mail-il1-x136.google.com with SMTP id e9e14a558f8ab-34bb72ffb1fso11141665ab.3 for ; Mon, 21 Aug 2023 18:55:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669322; x=1693274122; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=UmTCssMd/OkLNKuh8A+l/1O9kIjaudHJc+AQCzKHLlk=; b=A1fiRL9/gyGYLlkYcaWvN0fBKnQebciTf0B21CCdmsU1xEeOwPHiF1/xra5llF4iqQ QGiqLGX70eBqHNJ5suqvz4NbbitFDLqcy3w6HKepVcS2DlgpUM+PMtv50jv4oJX6cS0Z Y3Gnd49h1/o+WqJ4Dlgt0SeNoAFckPqhzGZ+Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669322; x=1693274122; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=UmTCssMd/OkLNKuh8A+l/1O9kIjaudHJc+AQCzKHLlk=; b=bdRfLzJByXLbZg2qGUct0WHQ2wZH176TAgNTMK6EvCvGWAqi7+cxGvB/0KJ3tTz0bG hge6Oh/yBHWgX2aQmK6JBGfd73dN3Q5n00MMtNdTuDX4FT5geAMfy/hqxzrT9njvT91p 5E7DQ7PqgU1yW3NaF4MHZ7lkOdzg2s/n7yxyQ0X9LJCR6Be+vy2n17D8k8IuUpZBLj5S lBfAWBeAPk5CQA5hnvCXfqZ4b69iT3vr8eWZOeCl/EJkBg7KOob8j2vwOcWL/plxZufW cD2W9yYEY0QMPj8aGem3ZPCh9B4Q41343YRiPwBgB6xyCVMDJKYrCx1NdnOpOHWBt/l6 RhaQ== X-Gm-Message-State: AOJu0YwMHwiTnriLroV0xIh0kWtuKXUWDU3sn54lHMHtuLkysu4MUVyz 4ZFfj4jcoAJspSXjWbESwlqy4A== X-Google-Smtp-Source: AGHT+IF3qvn51n/32NdS40F5GBEiAi2QwNfdcj7jaTRmqbaEocW2e2V/vyWF81PIpFzzD8zMdl/02g== X-Received: by 2002:a05:6e02:1a4b:b0:349:8dfa:ad64 with SMTP id u11-20020a056e021a4b00b003498dfaad64mr13813434ilv.15.1692669322088; Mon, 21 Aug 2023 18:55:22 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:21 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 2/7] mm/mremap: Allow moves within the same VMA Date: Tue, 22 Aug 2023 01:54:55 +0000 Message-ID: <20230822015501.791637-3-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org For the stack move happening in shift_arg_pages(), the move is happening within the same VMA which spans the old and new ranges. In case the aligned address happens to fall within that VMA, allow such moves and don't abort the optimization. In the mremap case, we cannot allow any such moves as will end up destroying some part of the mapping (either the source of the move, or part of the existing mapping). So just avoid it for mremap. Signed-off-by: Joel Fernandes (Google) --- fs/exec.c | 2 +- include/linux/mm.h | 2 +- mm/mremap.c | 29 +++++++++++++++-------------- 3 files changed, 17 insertions(+), 16 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 1a827d55ba94..244925307958 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -712,7 +712,7 @@ static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift) * process cleanup to remove whatever mess we made. */ if (length != move_page_tables(vma, old_start, - vma, new_start, length, false)) + vma, new_start, length, false, true)) return -ENOMEM; lru_add_drain(); diff --git a/include/linux/mm.h b/include/linux/mm.h index 406ab9ea818f..e635d1fc73b6 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2458,7 +2458,7 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen); extern unsigned long move_page_tables(struct vm_area_struct *vma, unsigned long old_addr, struct vm_area_struct *new_vma, unsigned long new_addr, unsigned long len, - bool need_rmap_locks); + bool need_rmap_locks, bool for_stack); /* * Flags used by change_protection(). For now we make it a bitmap so diff --git a/mm/mremap.c b/mm/mremap.c index 035fbf542a8f..06baa13bd2c8 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -490,12 +490,13 @@ static bool move_pgt_entry(enum pgt_entry entry, struct vm_area_struct *vma, } /* - * A helper to check if a previous mapping exists. Required for - * move_page_tables() and realign_addr() to determine if a previous mapping - * exists before we can do realignment optimizations. + * A helper to check if aligning down is OK. The aligned address should fall + * on *no mapping*. For the stack moving down, that's a special move within + * the VMA that is created to span the source and destination of the move, + * so we make an exception for it. */ static bool can_align_down(struct vm_area_struct *vma, unsigned long addr_to_align, - unsigned long mask) + unsigned long mask, bool for_stack) { unsigned long addr_masked = addr_to_align & mask; @@ -504,7 +505,7 @@ static bool can_align_down(struct vm_area_struct *vma, unsigned long addr_to_ali * of the corresponding VMA, we can't align down or we will destroy part * of the current mapping. */ - if (vma->vm_start != addr_to_align) + if (!for_stack && vma->vm_start != addr_to_align) return false; /* @@ -517,7 +518,7 @@ static bool can_align_down(struct vm_area_struct *vma, unsigned long addr_to_ali /* Opportunistically realign to specified boundary for faster copy. */ static void try_realign_addr(unsigned long *old_addr, struct vm_area_struct *old_vma, unsigned long *new_addr, struct vm_area_struct *new_vma, - unsigned long mask) + unsigned long mask, bool for_stack) { /* Skip if the addresses are already aligned. */ if ((*old_addr & ~mask) == 0) @@ -528,8 +529,8 @@ static void try_realign_addr(unsigned long *old_addr, struct vm_area_struct *old return; /* Ensure realignment doesn't cause overlap with existing mappings. */ - if (!can_align_down(old_vma, *old_addr, mask) || - !can_align_down(new_vma, *new_addr, mask)) + if (!can_align_down(old_vma, *old_addr, mask, for_stack) || + !can_align_down(new_vma, *new_addr, mask, for_stack)) return; *old_addr = *old_addr & mask; @@ -539,7 +540,7 @@ static void try_realign_addr(unsigned long *old_addr, struct vm_area_struct *old unsigned long move_page_tables(struct vm_area_struct *vma, unsigned long old_addr, struct vm_area_struct *new_vma, unsigned long new_addr, unsigned long len, - bool need_rmap_locks) + bool need_rmap_locks, bool for_stack) { unsigned long extent, old_end; struct mmu_notifier_range range; @@ -559,9 +560,9 @@ unsigned long move_page_tables(struct vm_area_struct *vma, * If possible, realign addresses to PMD boundary for faster copy. * Only realign if the mremap copying hits a PMD boundary. */ - if ((vma != new_vma) - && (len >= PMD_SIZE - (old_addr & ~PMD_MASK))) - try_realign_addr(&old_addr, vma, &new_addr, new_vma, PMD_MASK); + if (len >= PMD_SIZE - (old_addr & ~PMD_MASK)) + try_realign_addr(&old_addr, vma, &new_addr, new_vma, PMD_MASK, + for_stack); flush_cache_range(vma, old_addr, old_end); mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma->vm_mm, @@ -708,7 +709,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, } moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len, - need_rmap_locks); + need_rmap_locks, false); if (moved_len < old_len) { err = -ENOMEM; } else if (vma->vm_ops && vma->vm_ops->mremap) { @@ -722,7 +723,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, * and then proceed to unmap new area instead of old. */ move_page_tables(new_vma, new_addr, vma, old_addr, moved_len, - true); + true, false); vma = new_vma; old_len = new_len; old_addr = new_addr; From patchwork Tue Aug 22 01:54:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360067 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 651D9EE4996 for ; Tue, 22 Aug 2023 01:55:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232176AbjHVBz0 (ORCPT ); Mon, 21 Aug 2023 21:55:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232173AbjHVBzZ (ORCPT ); Mon, 21 Aug 2023 21:55:25 -0400 Received: from mail-il1-x133.google.com (mail-il1-x133.google.com [IPv6:2607:f8b0:4864:20::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D219A180 for ; Mon, 21 Aug 2023 18:55:23 -0700 (PDT) Received: by mail-il1-x133.google.com with SMTP id e9e14a558f8ab-34ca07ea55dso8942815ab.2 for ; Mon, 21 Aug 2023 18:55:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669323; x=1693274123; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=7MVDg4AiFSlG/+H1Z+4rrwZ5TuiaCol/qVRe1MkiyJ4=; b=dfaWwvA9oBL1IZ1Ld8nmBYZfchopf8juXDP2xXzgSG1+4P+Y22COL076a6tOgVMiwz QILZngUNHyArlcv/oP21Fea28QqZgLAOBnLUlGNmpK8m4daK64fIorApmoM/BsiyrFBx m5xcXJdKn0E99mRIBpuKTVuUQA71ez3oXSMYA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669323; x=1693274123; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=7MVDg4AiFSlG/+H1Z+4rrwZ5TuiaCol/qVRe1MkiyJ4=; b=HzDBWyAE+gJZaHDErVjYWgZz9MLc7uCraSpXRd/nxedFXA//p8WTv5Q/xYQlNbs7IN v8EgCh+a5FRm43LkDfjfys3wJMc2JBtBaZ8viem3GqRyoZp6plcIywDjpLXTRoJewNEP 7a2G11DSNAMCRnT21Vf9EAmoMB9M3Y6KRYtgHMUN+swzfSJjoWMat3ZFJ/9HguoXrbfr U2HdGGHASCKreZtYkFMssUpnX84nuqzOAIbuAoSeTH89mJyD4yGkq2jE9vTS/+bZueQw tf7+G1kP+blLEOHgXMb5WPpr+1QFKsWiCoGUXnz5j5aKD0PhRdYuolaRfcSrGEbLdQy0 tNWw== X-Gm-Message-State: AOJu0YyLK1ANPiwKc9fo6vGhuGnPxquJH3DAEnonacgu4o9n8/DsRB2C YAkryrW9IB+1zlE1UrM6q5kanQ== X-Google-Smtp-Source: AGHT+IHvqVdYTC6n4DObVG1/cE1N4x7Ela2mYdMwjClLo2WnnHgsjk7IpjhEewtQDpWgbd40PsHlhw== X-Received: by 2002:a05:6e02:1906:b0:345:b923:971b with SMTP id w6-20020a056e02190600b00345b923971bmr12162039ilu.3.1692669323174; Mon, 21 Aug 2023 18:55:23 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:22 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 3/7] selftests: mm: Fix failure case when new remap region was not found Date: Tue, 22 Aug 2023 01:54:56 +0000 Message-ID: <20230822015501.791637-4-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When a valid remap region could not be found, the source mapping is not cleaned up. Fix the goto statement such that the clean up happens. Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- tools/testing/selftests/mm/mremap_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 5c3773de9f0f..6822d657f589 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -316,7 +316,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, if (addr + c.dest_alignment < addr) { ksft_print_msg("Couldn't find a valid region to remap to\n"); ret = -1; - goto out; + goto clean_up_src; } addr += c.dest_alignment; } From patchwork Tue Aug 22 01:54:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360068 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 A25ADEE4996 for ; Tue, 22 Aug 2023 01:55:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232200AbjHVBzr (ORCPT ); Mon, 21 Aug 2023 21:55:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232177AbjHVBz0 (ORCPT ); Mon, 21 Aug 2023 21:55:26 -0400 Received: from mail-io1-xd34.google.com (mail-io1-xd34.google.com [IPv6:2607:f8b0:4864:20::d34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E36E613E for ; Mon, 21 Aug 2023 18:55:24 -0700 (PDT) Received: by mail-io1-xd34.google.com with SMTP id ca18e2360f4ac-7923dbb66aeso35049839f.2 for ; Mon, 21 Aug 2023 18:55:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669324; x=1693274124; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=u/QIpV5GdoUntyQD+YAulEqEr5HWAYhIt+wE2vL+NDs=; b=XkzwrKY2BPO8OgeQrtUkfRLAKPdqR5M18ZKGU4FGFYxvzWBQw/eRILHendM5mzgczx BYc3zziDMJlYLqaCnwu/53EUEoReNctpO9RDz4aY9+4UOxQi20TdBSerToh1EPXlQG2U E93hf56fnUcks90HI5CRHcJwgSm33hqntG3Xo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669324; x=1693274124; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=u/QIpV5GdoUntyQD+YAulEqEr5HWAYhIt+wE2vL+NDs=; b=AZB/RsZqMVXeFCv1uvn7mrHrefxkGbquhPEZJwFT0pYNmZOn135csaGKQynjZxp0yq 7eiYmnEFaojP0+e3F6JZeYcAlCdqwkeRRVBKhjcQPgGLABoLLu8YdiiAaYTtHRMu1kZU bQc6gnhS4d8cKJYq1tYxZQU+FmOQrYGn2HAtpHqrzJ8fgbwyTFMFQtCcuTZcFEPJcCyp rAdU7UmsR6Ot0PpA6hJJdRflrfFSxl7xPcAu/rPml9E/2U5wzNYO6lqHPNva+1M3l2Pp ECNVQqv/QbwJ05LG4iUjEQEqNUmz7LY8Z7WZLZ1yNFSQcYiTPrAkqWe/7projUg7JCm+ ZXOA== X-Gm-Message-State: AOJu0YzJYfUMjvxSgkNP/JIXSaKgRtWARKk+ZbCMRfAfUztBGWJz3xjP AU3uMeurZfTHOZdt1IuiRn0idQ== X-Google-Smtp-Source: AGHT+IH/MZvRRV4VaPoT76ACeI7st3J3G1ER7zfxqE1rsoOojx8UWxh8tAIJJ7hX3Eu9rNxe5sWekA== X-Received: by 2002:a05:6e02:2189:b0:349:2bab:9e47 with SMTP id j9-20020a056e02218900b003492bab9e47mr10720872ila.12.1692669324214; Mon, 21 Aug 2023 18:55:24 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:23 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 4/7] selftests: mm: Add a test for mutually aligned moves > PMD size Date: Tue, 22 Aug 2023 01:54:57 +0000 Message-ID: <20230822015501.791637-5-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org This patch adds a test case to check if a PMD-alignment optimization successfully happens. I add support to make sure there is some room before the source mapping, otherwise the optimization to trigger PMD-aligned move will be disabled as the kernel will detect that a mapping before the source exists and such optimization becomes impossible. Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- tools/testing/selftests/mm/mremap_test.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 6822d657f589..6304eb0947a3 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -44,6 +44,7 @@ enum { _1MB = 1ULL << 20, _2MB = 2ULL << 20, _4MB = 4ULL << 20, + _5MB = 5ULL << 20, _1GB = 1ULL << 30, _2GB = 2ULL << 30, PMD = _2MB, @@ -235,6 +236,11 @@ static void *get_source_mapping(struct config c) unsigned long long mmap_min_addr; mmap_min_addr = get_mmap_min_addr(); + /* + * For some tests, we need to not have any mappings below the + * source mapping. Add some headroom to mmap_min_addr for this. + */ + mmap_min_addr += 10 * _4MB; retry: addr += c.src_alignment; @@ -434,7 +440,7 @@ static int parse_args(int argc, char **argv, unsigned int *threshold_mb, return 0; } -#define MAX_TEST 13 +#define MAX_TEST 14 #define MAX_PERF_TEST 3 int main(int argc, char **argv) { @@ -500,6 +506,10 @@ int main(int argc, char **argv) test_cases[12] = MAKE_TEST(PUD, PUD, _2GB, NON_OVERLAPPING, EXPECT_SUCCESS, "2GB mremap - Source PUD-aligned, Destination PUD-aligned"); + /* Src and Dest addr 1MB aligned. 5MB mremap. */ + test_cases[13] = MAKE_TEST(_1MB, _1MB, _5MB, NON_OVERLAPPING, EXPECT_SUCCESS, + "5MB mremap - Source 1MB-aligned, Destination 1MB-aligned"); + perf_test_cases[0] = MAKE_TEST(page_size, page_size, _1GB, NON_OVERLAPPING, EXPECT_SUCCESS, "1GB mremap - Source PTE-aligned, Destination PTE-aligned"); /* From patchwork Tue Aug 22 01:54:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360069 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 56BB0EE4996 for ; Tue, 22 Aug 2023 01:55:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232207AbjHVBzs (ORCPT ); Mon, 21 Aug 2023 21:55:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232193AbjHVBzq (ORCPT ); Mon, 21 Aug 2023 21:55:46 -0400 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5553189 for ; Mon, 21 Aug 2023 18:55:25 -0700 (PDT) Received: by mail-il1-x134.google.com with SMTP id e9e14a558f8ab-34cacab5e33so5168275ab.2 for ; Mon, 21 Aug 2023 18:55:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669325; x=1693274125; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Axho/C2d3GxLBo+LZnFUqjVo2BRyImetugTXkfwiHhM=; b=dcsD/55UXOmDc6JKsWv76PEhXAR+DHegc6mDX9k2Jt5pnmj+7kdpAShITM6SWA8XVM +P0Xr5RhvhwbMxDE/FrWsVMmWu1bcOxe96a9Sj6svTHwHS6oAJLaYFyQ1ynl3xKLRc8F pQ+Bm6+1vG8lQOIPDNwuUzZJIUNfw4RUA4nHM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669325; x=1693274125; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Axho/C2d3GxLBo+LZnFUqjVo2BRyImetugTXkfwiHhM=; b=B9g3DkALZYAfXkMtFV1nWwfPSSpmWe9/Rv96g8PGPDk7ownI7igrG40CsyaUBxHRQg Ow/mOjJ9XauO7ut9qJCvTXkuuQ/jKFV4hS1xKThpCTv7U2lyKL8eLmA1ygIebyvBm4BY YNM1wVuADoHKfhi6C+a2E79v3yxML7zcRej9MWAwDWEHxkTaU+YsUB9j+BFXRMEwxRud /TTe38Omqt53xHdCaFV+dEKjYqdt2QPEztbSX42HpDuTiS0/I1lMfmRu02E7P8kO2rDc fWzzr2irJsJINiqQVBSIk+/ffhf0+6L37h6dgyDB1riBbts5LjS7xsO1H0U/Rq8jXiyR KWUQ== X-Gm-Message-State: AOJu0YxB3jjl6e99WdOeoR8sPK0+/8JQyl8rBVrjpt7pd2IqMHw55tF0 ECEdQQYE+dtkQVhuknOAMpHvFw== X-Google-Smtp-Source: AGHT+IGZXIerY8NUWYReuIPpDpvFlLHcIDml9i8pszriAMC0UzQ9sup1GqyFJEY4NY5BpU4X49RLVw== X-Received: by 2002:a05:6e02:dce:b0:349:a4f8:8815 with SMTP id l14-20020a056e020dce00b00349a4f88815mr9945123ilj.2.1692669325296; Mon, 21 Aug 2023 18:55:25 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:24 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 5/7] selftests: mm: Add a test for remapping to area immediately after existing mapping Date: Tue, 22 Aug 2023 01:54:58 +0000 Message-ID: <20230822015501.791637-6-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org This patch adds support for verifying that we correctly handle the situation where something is already mapped before the destination of the remap. Any realignment of destination address and PMD-copy will destroy that existing mapping. In such cases, we need to avoid doing the optimization. To test this, we map an area called the preamble before the remap region. Then we verify after the mremap operation that this region did not get corrupted. Putting some prints in the kernel, I verified that we optimize correctly in different situations: Optimize when there is alignment and no previous mapping (this is tested by previous patch). can_align_down(old_vma->vm_start=2900000, old_addr=2900000, mask=-2097152): 0 can_align_down(new_vma->vm_start=2f00000, new_addr=2f00000, mask=-2097152): 0 === Starting move_page_tables === Doing PUD move for 2800000 -> 2e00000 of extent=200000 <-- Optimization Doing PUD move for 2a00000 -> 3000000 of extent=200000 Doing PUD move for 2c00000 -> 3200000 of extent=200000 Don't optimize when there is alignment but there is previous mapping (this is tested by this patch). Notice that can_align_down() returns 1 for the destination mapping as we detected there is something there. can_align_down(old_vma->vm_start=2900000, old_addr=2900000, mask=-2097152): 0 can_align_down(new_vma->vm_start=5700000, new_addr=5700000, mask=-2097152): 1 === Starting move_page_tables === Doing move_ptes for 2900000 -> 5700000 of extent=100000 <-- Unoptimized Doing PUD move for 2a00000 -> 5800000 of extent=200000 Doing PUD move for 2c00000 -> 5a00000 of extent=200000 Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- tools/testing/selftests/mm/mremap_test.c | 57 +++++++++++++++++++++--- 1 file changed, 52 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 6304eb0947a3..d7366074e2a8 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -29,6 +29,7 @@ struct config { unsigned long long dest_alignment; unsigned long long region_size; int overlapping; + int dest_preamble_size; }; struct test { @@ -283,7 +284,7 @@ static void *get_source_mapping(struct config c) static long long remap_region(struct config c, unsigned int threshold_mb, char pattern_seed) { - void *addr, *src_addr, *dest_addr; + void *addr, *src_addr, *dest_addr, *dest_preamble_addr; unsigned long long i; struct timespec t_start = {0, 0}, t_end = {0, 0}; long long start_ns, end_ns, align_mask, ret, offset; @@ -300,7 +301,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, goto out; } - /* Set byte pattern */ + /* Set byte pattern for source block. */ srand(pattern_seed); for (i = 0; i < threshold; i++) memset((char *) src_addr + i, (char) rand(), 1); @@ -312,6 +313,9 @@ static long long remap_region(struct config c, unsigned int threshold_mb, addr = (void *) (((unsigned long long) src_addr + c.region_size + offset) & align_mask); + /* Remap after the destination block preamble. */ + addr += c.dest_preamble_size; + /* See comment in get_source_mapping() */ if (!((unsigned long long) addr & c.dest_alignment)) addr = (void *) ((unsigned long long) addr | c.dest_alignment); @@ -327,6 +331,24 @@ static long long remap_region(struct config c, unsigned int threshold_mb, addr += c.dest_alignment; } + if (c.dest_preamble_size) { + dest_preamble_addr = mmap((void *) addr - c.dest_preamble_size, c.dest_preamble_size, + PROT_READ | PROT_WRITE, + MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED, + -1, 0); + if (dest_preamble_addr == MAP_FAILED) { + ksft_print_msg("Failed to map dest preamble region: %s\n", + strerror(errno)); + ret = -1; + goto clean_up_src; + } + + /* Set byte pattern for the dest preamble block. */ + srand(pattern_seed); + for (i = 0; i < c.dest_preamble_size; i++) + memset((char *) dest_preamble_addr + i, (char) rand(), 1); + } + clock_gettime(CLOCK_MONOTONIC, &t_start); dest_addr = mremap(src_addr, c.region_size, c.region_size, MREMAP_MAYMOVE|MREMAP_FIXED, (char *) addr); @@ -335,7 +357,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, if (dest_addr == MAP_FAILED) { ksft_print_msg("mremap failed: %s\n", strerror(errno)); ret = -1; - goto clean_up_src; + goto clean_up_dest_preamble; } /* Verify byte pattern after remapping */ @@ -353,6 +375,23 @@ static long long remap_region(struct config c, unsigned int threshold_mb, } } + /* Verify the dest preamble byte pattern after remapping */ + if (c.dest_preamble_size) { + srand(pattern_seed); + for (i = 0; i < c.dest_preamble_size; i++) { + char c = (char) rand(); + + if (((char *) dest_preamble_addr)[i] != c) { + ksft_print_msg("Preamble data after remap doesn't match at offset %d\n", + i); + ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff, + ((char *) dest_preamble_addr)[i] & 0xff); + ret = -1; + goto clean_up_dest; + } + } + } + start_ns = t_start.tv_sec * NS_PER_SEC + t_start.tv_nsec; end_ns = t_end.tv_sec * NS_PER_SEC + t_end.tv_nsec; ret = end_ns - start_ns; @@ -365,6 +404,9 @@ static long long remap_region(struct config c, unsigned int threshold_mb, */ clean_up_dest: munmap(dest_addr, c.region_size); +clean_up_dest_preamble: + if (c.dest_preamble_size && dest_preamble_addr) + munmap(dest_preamble_addr, c.dest_preamble_size); clean_up_src: munmap(src_addr, c.region_size); out: @@ -440,7 +482,7 @@ static int parse_args(int argc, char **argv, unsigned int *threshold_mb, return 0; } -#define MAX_TEST 14 +#define MAX_TEST 15 #define MAX_PERF_TEST 3 int main(int argc, char **argv) { @@ -449,7 +491,7 @@ int main(int argc, char **argv) unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD; unsigned int pattern_seed; int num_expand_tests = 2; - struct test test_cases[MAX_TEST]; + struct test test_cases[MAX_TEST] = {}; struct test perf_test_cases[MAX_PERF_TEST]; int page_size; time_t t; @@ -510,6 +552,11 @@ int main(int argc, char **argv) test_cases[13] = MAKE_TEST(_1MB, _1MB, _5MB, NON_OVERLAPPING, EXPECT_SUCCESS, "5MB mremap - Source 1MB-aligned, Destination 1MB-aligned"); + /* Src and Dest addr 1MB aligned. 5MB mremap. */ + test_cases[14] = MAKE_TEST(_1MB, _1MB, _5MB, NON_OVERLAPPING, EXPECT_SUCCESS, + "5MB mremap - Source 1MB-aligned, Dest 1MB-aligned with 40MB Preamble"); + test_cases[14].config.dest_preamble_size = 10 * _4MB; + perf_test_cases[0] = MAKE_TEST(page_size, page_size, _1GB, NON_OVERLAPPING, EXPECT_SUCCESS, "1GB mremap - Source PTE-aligned, Destination PTE-aligned"); /* From patchwork Tue Aug 22 01:54:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360070 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 339DFEE49AA for ; Tue, 22 Aug 2023 01:55:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232193AbjHVBzt (ORCPT ); Mon, 21 Aug 2023 21:55:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232195AbjHVBzq (ORCPT ); Mon, 21 Aug 2023 21:55:46 -0400 Received: from mail-il1-x131.google.com (mail-il1-x131.google.com [IPv6:2607:f8b0:4864:20::131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2649A194 for ; Mon, 21 Aug 2023 18:55:27 -0700 (PDT) Received: by mail-il1-x131.google.com with SMTP id e9e14a558f8ab-34ca63f6a27so6271005ab.1 for ; Mon, 21 Aug 2023 18:55:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669326; x=1693274126; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=FD9aGvqokkyzhhNkz6Ym1Row+eZXw3mkXyW6dIKtxjg=; b=BVxKaBwCWqmv9ynuQE7s7YtVK38FkX779KlBkPDkQBjoFlq8GAIqxdpbPgdXIHuYEP sTZl8JURdoNTsMC+vviGXqt9EnyyK4mtdmmYuLB06JdlbsUAxre1uPUPQ9095aYWBBzQ UX41cyoBUmNRAXgSpAygarUMAnDMlAVDQL8Lk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669326; x=1693274126; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=FD9aGvqokkyzhhNkz6Ym1Row+eZXw3mkXyW6dIKtxjg=; b=VtI9bLyqikS0s6RqZKJh2I2jVAHA2iBcqGOZpomt/ECMXCTv35oxXm0or48f8zzSHc HU5GXHHHym2xsNmeIkPuS1leCnAXtgb1oylBVT5qBQn1eaLLduc8cs+T2bAbPr+y+BYX Yloi5LX2cACE7JIGBvQCVcajXLchS2M7CYmXUMNPXwzDNJ4KDOBRg8Ss7hpQl5Zr2BP3 FSERA/5ckQ4zBVWoQOl2xgIOPX//LJyZ/6dsLmbN7kA3usyEcEP1eP2BemNRv9+MMOEm 9RYi/STtPOaPt+9u0f+GwNcyg17t6Yz5w+rPThsnqInqspwwc9hiPgipmVFsJ+tiVx32 M5tQ== X-Gm-Message-State: AOJu0YyG8iNGb9Y7Vac0AXHZ/3gP4MLBnyjdJIbrpaLaQ8YDtiGdRCXz tF6MSCndSETL/L50/UeO1D8nuw== X-Google-Smtp-Source: AGHT+IHvcEbCoDqCw1Fy8RgEWPuit/xENlfoh2EHuYOQYRSjxZ82L50BdV84tK7DyIjYWJTuRfLE/Q== X-Received: by 2002:a05:6e02:190d:b0:346:1185:31d0 with SMTP id w13-20020a056e02190d00b00346118531d0mr11455463ilu.9.1692669326463; Mon, 21 Aug 2023 18:55:26 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:25 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 6/7] selftests: mm: Add a test for remapping within a range Date: Tue, 22 Aug 2023 01:54:59 +0000 Message-ID: <20230822015501.791637-7-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Move a block of memory within a memory range. Any alignment optimization on the source address may cause corruption. Verify using kselftest that it works. I have also verified with tracing that such optimization does not happen due to this check in can_align_down(): if (!for_stack && vma->vm_start <= addr_masked) return false; Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- tools/testing/selftests/mm/mremap_test.c | 79 +++++++++++++++++++++++- 1 file changed, 78 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index d7366074e2a8..f45d1abedc9c 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -23,6 +23,7 @@ #define VALIDATION_NO_THRESHOLD 0 /* Verify the entire region */ #define MIN(X, Y) ((X) < (Y) ? (X) : (Y)) +#define SIZE_MB(m) ((size_t)m * (1024 * 1024)) struct config { unsigned long long src_alignment; @@ -226,6 +227,79 @@ static void mremap_expand_merge_offset(FILE *maps_fp, unsigned long page_size) ksft_test_result_fail("%s\n", test_name); } +/* + * Verify that an mremap within a range does not cause corruption + * of unrelated part of range. + * + * Consider the following range which is 2MB aligned and is + * a part of a larger 10MB range which is not shown. Each + * character is 256KB below making the source and destination + * 2MB each. The lower case letters are moved (s to d) and the + * upper case letters are not moved. The below test verifies + * that the upper case S letters are not corrupted by the + * adjacent mremap. + * + * |DDDDddddSSSSssss| + */ +static void mremap_move_within_range(char pattern_seed) +{ + char *test_name = "mremap mremap move within range"; + void *src, *dest; + int i, success = 1; + + size_t size = SIZE_MB(20); + void *ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (ptr == MAP_FAILED) { + perror("mmap"); + success = 0; + goto out; + } + memset(ptr, 0, size); + + src = ptr + SIZE_MB(6); + src = (void *)((unsigned long)src & ~(SIZE_MB(2) - 1)); + + /* Set byte pattern for source block. */ + srand(pattern_seed); + for (i = 0; i < SIZE_MB(2); i++) { + ((char *)src)[i] = (char) rand(); + } + + dest = src - SIZE_MB(2); + + void *new_ptr = mremap(src + SIZE_MB(1), SIZE_MB(1), SIZE_MB(1), + MREMAP_MAYMOVE | MREMAP_FIXED, dest + SIZE_MB(1)); + if (new_ptr == MAP_FAILED) { + perror("mremap"); + success = 0; + goto out; + } + + /* Verify byte pattern after remapping */ + srand(pattern_seed); + for (i = 0; i < SIZE_MB(1); i++) { + char c = (char) rand(); + + if (((char *)src)[i] != c) { + ksft_print_msg("Data at src at %d got corrupted due to unrelated mremap\n", + i); + ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff, + ((char *) src)[i] & 0xff); + success = 0; + } + } + +out: + if (munmap(ptr, size) == -1) + perror("munmap"); + + if (success) + ksft_test_result_pass("%s\n", test_name); + else + ksft_test_result_fail("%s\n", test_name); +} + /* * Returns the start address of the mapping on success, else returns * NULL on failure. @@ -491,6 +565,7 @@ int main(int argc, char **argv) unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD; unsigned int pattern_seed; int num_expand_tests = 2; + int num_misc_tests = 1; struct test test_cases[MAX_TEST] = {}; struct test perf_test_cases[MAX_PERF_TEST]; int page_size; @@ -572,7 +647,7 @@ int main(int argc, char **argv) (threshold_mb * _1MB >= _1GB); ksft_set_plan(ARRAY_SIZE(test_cases) + (run_perf_tests ? - ARRAY_SIZE(perf_test_cases) : 0) + num_expand_tests); + ARRAY_SIZE(perf_test_cases) : 0) + num_expand_tests + num_misc_tests); for (i = 0; i < ARRAY_SIZE(test_cases); i++) run_mremap_test_case(test_cases[i], &failures, threshold_mb, @@ -590,6 +665,8 @@ int main(int argc, char **argv) fclose(maps_fp); + mremap_move_within_range(pattern_seed); + if (run_perf_tests) { ksft_print_msg("\n%s\n", "mremap HAVE_MOVE_PMD/PUD optimization time comparison for 1GB region:"); From patchwork Tue Aug 22 01:55:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 13360071 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 BAE24EE49A6 for ; Tue, 22 Aug 2023 01:56:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231459AbjHVB4n (ORCPT ); Mon, 21 Aug 2023 21:56:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232172AbjHVBzs (ORCPT ); Mon, 21 Aug 2023 21:55:48 -0400 Received: from mail-il1-x135.google.com (mail-il1-x135.google.com [IPv6:2607:f8b0:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2356F1A1 for ; Mon, 21 Aug 2023 18:55:28 -0700 (PDT) Received: by mail-il1-x135.google.com with SMTP id e9e14a558f8ab-34bbc5eb310so11406125ab.2 for ; Mon, 21 Aug 2023 18:55:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1692669327; x=1693274127; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=XSp2RkE7WNDbZkDSniptEmg1knVa7eiFGdAlEcTCYXk=; b=hB3OrYAbWCivFEMRY0ZLiMpZipo0ohQ9va0ALoFrxF3N6j0sGBBJlAMhPCHbROrmOG MMW9Vz6sZFa1UpuJWvtJjqpcBgMy1oMCAqHWjDG602AT6TI0cyy2YQgsTV3s8EI+m5+o Y3Mr4kc1PezfoD+BPHuwn4CF5Y65DFcuRKn00= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692669327; x=1693274127; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=XSp2RkE7WNDbZkDSniptEmg1knVa7eiFGdAlEcTCYXk=; b=G6iOejmREpBXlsCvJs11jGla8dtNp+CFyoNMM0EsKhhMZE0RKZZwlxaB/GebA2XkxF gqXU9KxcLayFA1yW/5zAxUdkrSw0vRX7QIS8xPCR3rM5QPBATyjUQCVAWNY1CwsAaDKJ xiHg/X57vHQG8UNCFl2qx4Eix/9hCx1SaAZVeGfZcyKo+FXjjw/b1FCOEg3FmvmCTHZ5 BZ5Cd7M364m9sUGlJGkfkAHcDScsbvU8QQzeZJywqC1rxS7sUqy0EQ6cpqLWS69o9QRg 28bYKpD8+MZyymb3o/bhPijniB4QbWqKrikf02bO9lQIvMg4jfxfU4/aLpun4c7V77O7 Ryow== X-Gm-Message-State: AOJu0Yy+X1lLVyveQQeE20vfNaT3Q9oyBYZR9DFT5LXw0wuky+hGk7Nq k76YMDLqhRjXgBprY16yEbZdqQ== X-Google-Smtp-Source: AGHT+IHh2CBbyhDqgwo/dvz/3E91EJeozSUIuQC8LNJTxnm78FkGwumtTjDlvLHNyDKvyt16yZrJFg== X-Received: by 2002:a05:6e02:e02:b0:346:5e80:bf67 with SMTP id a2-20020a056e020e0200b003465e80bf67mr8883734ilk.21.1692669327493; Mon, 21 Aug 2023 18:55:27 -0700 (PDT) Received: from joelboxx5.c.googlers.com.com (156.190.123.34.bc.googleusercontent.com. [34.123.190.156]) by smtp.gmail.com with ESMTPSA id q11-20020a92d40b000000b0034886587bdcsm2907390ilm.18.2023.08.21.18.55.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Aug 2023 18:55:26 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: Joel Fernandes , linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Shuah Khan , Vlastimil Babka , Michal Hocko , Linus Torvalds , Lorenzo Stoakes , Kirill A Shutemov , "Liam R. Howlett" , "Paul E. McKenney" , Suren Baghdasaryan , Kalesh Singh , Lokesh Gidra Subject: [PATCH v5 7/7] selftests: mm: Add a test for moving from an offset from start of mapping Date: Tue, 22 Aug 2023 01:55:00 +0000 Message-ID: <20230822015501.791637-8-joel@joelfernandes.org> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230822015501.791637-1-joel@joelfernandes.org> References: <20230822015501.791637-1-joel@joelfernandes.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Joel Fernandes It is possible that the aligned address falls on no existing mapping, however that does not mean that we can just align it down to that. This test verifies that the "vma->vm_start != addr_to_align" check in can_align_down() prevents disastrous results if aligning down when source and dest are mutually aligned within a PMD but the source/dest addresses requested are not at the beginning of the respective mapping containing these addresses. Signed-off-by: Joel Fernandes (Google) Reviewed-by: Lorenzo Stoakes --- tools/testing/selftests/mm/mremap_test.c | 189 ++++++++++++++++------- 1 file changed, 134 insertions(+), 55 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index f45d1abedc9c..c71ac8306c89 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -24,6 +24,7 @@ #define MIN(X, Y) ((X) < (Y) ? (X) : (Y)) #define SIZE_MB(m) ((size_t)m * (1024 * 1024)) +#define SIZE_KB(k) ((size_t)k * 1024) struct config { unsigned long long src_alignment; @@ -148,6 +149,60 @@ static bool is_range_mapped(FILE *maps_fp, void *start, void *end) return success; } +/* + * Returns the start address of the mapping on success, else returns + * NULL on failure. + */ +static void *get_source_mapping(struct config c) +{ + unsigned long long addr = 0ULL; + void *src_addr = NULL; + unsigned long long mmap_min_addr; + + mmap_min_addr = get_mmap_min_addr(); + /* + * For some tests, we need to not have any mappings below the + * source mapping. Add some headroom to mmap_min_addr for this. + */ + mmap_min_addr += 10 * _4MB; + +retry: + addr += c.src_alignment; + if (addr < mmap_min_addr) + goto retry; + + src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE, + MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED, + -1, 0); + if (src_addr == MAP_FAILED) { + if (errno == EPERM || errno == EEXIST) + goto retry; + goto error; + } + /* + * Check that the address is aligned to the specified alignment. + * Addresses which have alignments that are multiples of that + * specified are not considered valid. For instance, 1GB address is + * 2MB-aligned, however it will not be considered valid for a + * requested alignment of 2MB. This is done to reduce coincidental + * alignment in the tests. + */ + if (((unsigned long long) src_addr & (c.src_alignment - 1)) || + !((unsigned long long) src_addr & c.src_alignment)) { + munmap(src_addr, c.region_size); + goto retry; + } + + if (!src_addr) + goto error; + + return src_addr; +error: + ksft_print_msg("Failed to map source region: %s\n", + strerror(errno)); + return NULL; +} + /* * This test validates that merge is called when expanding a mapping. * Mapping containing three pages is created, middle page is unmapped @@ -300,60 +355,6 @@ static void mremap_move_within_range(char pattern_seed) ksft_test_result_fail("%s\n", test_name); } -/* - * Returns the start address of the mapping on success, else returns - * NULL on failure. - */ -static void *get_source_mapping(struct config c) -{ - unsigned long long addr = 0ULL; - void *src_addr = NULL; - unsigned long long mmap_min_addr; - - mmap_min_addr = get_mmap_min_addr(); - /* - * For some tests, we need to not have any mappings below the - * source mapping. Add some headroom to mmap_min_addr for this. - */ - mmap_min_addr += 10 * _4MB; - -retry: - addr += c.src_alignment; - if (addr < mmap_min_addr) - goto retry; - - src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE, - MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED, - -1, 0); - if (src_addr == MAP_FAILED) { - if (errno == EPERM || errno == EEXIST) - goto retry; - goto error; - } - /* - * Check that the address is aligned to the specified alignment. - * Addresses which have alignments that are multiples of that - * specified are not considered valid. For instance, 1GB address is - * 2MB-aligned, however it will not be considered valid for a - * requested alignment of 2MB. This is done to reduce coincidental - * alignment in the tests. - */ - if (((unsigned long long) src_addr & (c.src_alignment - 1)) || - !((unsigned long long) src_addr & c.src_alignment)) { - munmap(src_addr, c.region_size); - goto retry; - } - - if (!src_addr) - goto error; - - return src_addr; -error: - ksft_print_msg("Failed to map source region: %s\n", - strerror(errno)); - return NULL; -} - /* Returns the time taken for the remap on success else returns -1. */ static long long remap_region(struct config c, unsigned int threshold_mb, char pattern_seed) @@ -487,6 +488,83 @@ static long long remap_region(struct config c, unsigned int threshold_mb, return ret; } +/* + * Verify that an mremap aligning down does not destroy + * the beginning of the mapping just because the aligned + * down address landed on a mapping that maybe does not exist. + */ +static void mremap_move_1mb_from_start(char pattern_seed) +{ + char *test_name = "mremap move 1mb from start at 2MB+256KB aligned src"; + void *src = NULL, *dest = NULL; + int i, success = 1; + + /* Config to reuse get_source_mapping() to do an aligned mmap. */ + struct config c = { + .src_alignment = SIZE_MB(1) + SIZE_KB(256), + .region_size = SIZE_MB(6) + }; + + src = get_source_mapping(c); + if (!src) { + success = 0; + goto out; + } + + c.src_alignment = SIZE_MB(1) + SIZE_KB(256); + dest = get_source_mapping(c); + if (!dest) { + success = 0; + goto out; + } + + /* Set byte pattern for source block. */ + srand(pattern_seed); + for (i = 0; i < SIZE_MB(2); i++) { + ((char *)src)[i] = (char) rand(); + } + + /* + * Unmap the beginning of dest so that the aligned address + * falls on no mapping. + */ + munmap(dest, SIZE_MB(1)); + + void *new_ptr = mremap(src + SIZE_MB(1), SIZE_MB(1), SIZE_MB(1), + MREMAP_MAYMOVE | MREMAP_FIXED, dest + SIZE_MB(1)); + if (new_ptr == MAP_FAILED) { + perror("mremap"); + success = 0; + goto out; + } + + /* Verify byte pattern after remapping */ + srand(pattern_seed); + for (i = 0; i < SIZE_MB(1); i++) { + char c = (char) rand(); + + if (((char *)src)[i] != c) { + ksft_print_msg("Data at src at %d got corrupted due to unrelated mremap\n", + i); + ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff, + ((char *) src)[i] & 0xff); + success = 0; + } + } + +out: + if (src && munmap(src, c.region_size) == -1) + perror("munmap src"); + + if (dest && munmap(dest, c.region_size) == -1) + perror("munmap dest"); + + if (success) + ksft_test_result_pass("%s\n", test_name); + else + ksft_test_result_fail("%s\n", test_name); +} + static void run_mremap_test_case(struct test test_case, int *failures, unsigned int threshold_mb, unsigned int pattern_seed) @@ -565,7 +643,7 @@ int main(int argc, char **argv) unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD; unsigned int pattern_seed; int num_expand_tests = 2; - int num_misc_tests = 1; + int num_misc_tests = 2; struct test test_cases[MAX_TEST] = {}; struct test perf_test_cases[MAX_PERF_TEST]; int page_size; @@ -666,6 +744,7 @@ int main(int argc, char **argv) fclose(maps_fp); mremap_move_within_range(pattern_seed); + mremap_move_1mb_from_start(pattern_seed); if (run_perf_tests) { ksft_print_msg("\n%s\n",