From patchwork Mon Jan 26 12:00:43 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 5708871 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7837F9F1D6 for ; Mon, 26 Jan 2015 12:05:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2EE6F20121 for ; Mon, 26 Jan 2015 12:05:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D7AA1200E8 for ; Mon, 26 Jan 2015 12:05:55 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YFiOR-000324-R1; Mon, 26 Jan 2015 12:03:47 +0000 Received: from mta-out1.inet.fi ([62.71.2.203] helo=kirsi1.inet.fi) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YFiOM-0002D3-9o for linux-arm-kernel@lists.infradead.org; Mon, 26 Jan 2015 12:03:44 +0000 Received: from node.shutemov.name (80.220.224.16) by kirsi1.inet.fi (8.5.142.08) id 54BEDAFD00985391; Mon, 26 Jan 2015 14:00:49 +0200 Received: by node.shutemov.name (Postfix, from userid 1000) id EFDB740356; Mon, 26 Jan 2015 14:00:43 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=shutemov.name; s=default; t=1422273643; bh=/Oz4IoVduxfyiN3LMIRfkYbHhSlxnWvx5vAxmln+yIk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=QZq04WJ7NIAWCI6LJOAI9+TF/GD5/XVfM89lzjx8DIjuvnd6YUM9BJymTWhutGGdb msDlhHAysC9QLdWa1+IONX8gurxqmetA6PA3+fnhmLRM7YWSeVuDybk8LprzzxLAIT 5nvJtTZrtGXkRyvQ4L6ailjsI+BVfZXZI/L8KTQc= Date: Mon, 26 Jan 2015 14:00:43 +0200 From: "Kirill A. Shutemov" To: Nishanth Menon , Andrew Morton Subject: Re: [next-20150119]regression (mm)? Message-ID: <20150126120043.GB25833@node.dhcp.inet.fi> References: <20150120001643.7D15AA8@black.fi.intel.com> <20150120114555.GA11502@n2100.arm.linux.org.uk> <20150120140546.DDCB8D4@black.fi.intel.com> <20150123172736.GA15392@kahuna> <20150123183706.GA15791@kahuna> <20150123202229.GA9038@node.dhcp.inet.fi> <20150124011311.GB9038@node.dhcp.inet.fi> <20150124043746.GA22262@kahuna> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20150124043746.GA22262@kahuna> User-Agent: Mutt/1.5.23.1 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150126_040342_892593_7CED2847 X-CRM114-Status: GOOD ( 18.33 ) X-Spam-Score: 0.6 (/) Cc: James Hogan , Russell King - ARM Linux , Tyler Baker , Felipe Balbi , linux-mm@kvack.org, linux-next , "linux-arm-kernel@lists.infradead.org" , Guan Xuetao , linux-omap , "Kirill A. Shutemov" X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Fri, Jan 23, 2015 at 10:37:46PM -0600, Nishanth Menon wrote: > On 03:13-20150124, Kirill A. Shutemov wrote: > > > >> On 09:39-20150123, Tyler Baker wrote: > [...] > > > >> > I just reviewed the boot logs for next-20150123 and there still seems > > > >> > to be a related issue. I've been boot testing > > > >> > multi_v7_defconfig+CONFIG_ARM_LPAE=y kernel configurations which still > > > >> > seem broken. > [...] > > Okay, proof of concept patch is below. It's going to break every other > > architecture with FIRST_USER_ADDRESS != 0, but I think it's cleaner way to > > go. > > Testing on my end: > > just ran through this set (+ logs similar to Tyler's from my side): > > next-20150123 (multi_v7_defconfig == !LPAE) > 1: BeagleBoard-X15(am57xx-evm): BOOT: PASS: http://paste.ubuntu.org.cn/2219449 > 2: dra72x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2219450 > 3: dra7xx-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2219451 > 4: omap5-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2219452 > TOTAL = 4 boards, Booted Boards = 4, No Boot boards = 0 > > next-20150123-LPAE-Logging enabled[1] (multi_v7_defconfig +LPAE) > 1: BeagleBoard-X15(am57xx-evm): BOOT: FAIL: http://paste.ubuntu.org.cn/2220938 > 2: dra72x-evm: BOOT: FAIL: http://paste.ubuntu.org.cn/2220943 > 3: dra7xx-evm: BOOT: FAIL: http://paste.ubuntu.org.cn/2220947 > 4: omap5-evm: BOOT: FAIL: http://paste.ubuntu.org.cn/2220955 > TOTAL = 4 boards, Booted Boards = 0, No Boot boards = 4 > > next-20150123-LPAE-new-patch [2] (multi_v7_defconfig + LPAE) > 1: BeagleBoard-X15(am57xx-evm): BOOT: PASS: http://paste.ubuntu.org.cn/2221047 > 2: dra72x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221065 > 3: dra7xx-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221069 > 4: omap5-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221070 > TOTAL = 4 boards, Booted Boards = 4, No Boot boards = 0 > > next-20150123-new-patch[2] (multi_v7_defconfig == !LPAE) > 1: am335x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221277 > 2: am335x-sk: BOOT: PASS: http://paste.ubuntu.org.cn/2221278 > 3: am437x-sk: BOOT: FAIL: http://paste.ubuntu.org.cn/2221279 (unrelated) > 4: am43xx-epos: BOOT: PASS: http://paste.ubuntu.org.cn/2221280 > 5: am43xx-gpevm: BOOT: PASS: http://paste.ubuntu.org.cn/2221281 > 6: BeagleBoard-X15(am57xx-evm): BOOT: PASS: http://paste.ubuntu.org.cn/2221282 > 7: BeagleBoard-XM: BOOT: FAIL: http://paste.ubuntu.org.cn/2221283 (unrelated) > 8: beagleboard-vanilla: BOOT: PASS: http://paste.ubuntu.org.cn/2221284 > 9: beaglebone-black: BOOT: PASS: http://paste.ubuntu.org.cn/2221285 > 10: beaglebone: BOOT: FAIL: http://paste.ubuntu.org.cn/2221286 (unrelated) > 11: dra72x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221287 > 12: dra7xx-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221288 > 13: omap5-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221289 > 14: pandaboard-es: BOOT: PASS: http://paste.ubuntu.org.cn/2221290 > 15: pandaboard-vanilla: BOOT: PASS: http://paste.ubuntu.org.cn/2221291 > 16: sdp4430: BOOT: PASS: http://paste.ubuntu.org.cn/2221292 > TOTAL = 16 boards, Booted Boards = 13, No Boot boards = 3 > > next-20150123-new-patch[2] (omap2plus_defconfig) > 1: am335x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221653 > 2: am335x-sk: BOOT: PASS: http://paste.ubuntu.org.cn/2221654 > 3: am437x-sk: BOOT: PASS: http://paste.ubuntu.org.cn/2221656 > 4: am43xx-epos: BOOT: PASS: http://paste.ubuntu.org.cn/2221659 > 5: am43xx-gpevm: BOOT: PASS: http://paste.ubuntu.org.cn/2221660 > 6: BeagleBoard-X15(am57xx-evm): BOOT: PASS: http://paste.ubuntu.org.cn/2221661 > 7: BeagleBoard-XM: BOOT: PASS: http://paste.ubuntu.org.cn/2221670 > 8: beagleboard-vanilla: BOOT: PASS: http://paste.ubuntu.org.cn/2221676 > 9: beaglebone-black: BOOT: PASS: http://paste.ubuntu.org.cn/2221683 > 10: beaglebone: BOOT: PASS: http://paste.ubuntu.org.cn/2221690 > 11: dra72x-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221692 > 12: dra7xx-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221695 > 13: omap5-evm: BOOT: PASS: http://paste.ubuntu.org.cn/2221700 > 14: pandaboard-es: BOOT: PASS: http://paste.ubuntu.org.cn/2221704 > 15: pandaboard-vanilla: BOOT: PASS: http://paste.ubuntu.org.cn/2221707 > 16: sdp4430: BOOT: PASS: http://paste.ubuntu.org.cn/2221713 > TOTAL = 16 boards, Booted Boards = 16, No Boot boards = 0 Okay thanks. Here's proper patch. From 8f9845ab8d972164b700ff3e3ce53484cceb942b Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Mon, 26 Jan 2015 12:07:54 +0200 Subject: [PATCH 1/2] mm: fix false-positive warning on exit due mm_nr_pmds(mm) The problem is that we check nr_ptes/nr_pmds in exit_mmap() which happens *before* pgd_free(). And if an arch does pte/pmd allocation in pgd_alloc() and frees them in pgd_free() we see offset in counters by the time of the checks. We tried to workaround this by offsetting expected counter value according to FIRST_USER_ADDRESS for both nr_pte and nr_pmd in exit_mmap(). But it doesn't work in some cases: 1. ARM with LPAE enabled also has non-zero USER_PGTABLES_CEILING, but upper addresses occupied with huge pmd entries, so the trick with offsetting expected counter value will get really ugly: we will have to apply it nr_pmds, but not nr_ptes. 2. Metag has non-zero FIRST_USER_ADDRESS, but doesn't do allocation pte/pmd page tables allocation in pgd_alloc(), just setup a pgd entry which is allocated at boot and shared accross all processes. The proposal is to move the check to check_mm() which happens *after* pgd_free() and do proper accounting during pgd_alloc() and pgd_free() which would bring counters to zero if nothing leaked. Signed-off-by: Kirill A. Shutemov Reported-by: Tyler Baker Tested-by: Nishanth Menon Cc: Russell King Cc: James Hogan Cc: Guan Xuetao Tested-by: Tyler Baker --- arch/arm/mm/pgd.c | 4 ++++ arch/unicore32/mm/pgd.c | 3 +++ kernel/fork.c | 8 ++++++++ mm/mmap.c | 5 ----- 4 files changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index 249379535be2..a3681f11dd9f 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -97,6 +97,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) no_pte: pmd_free(mm, new_pmd); + mm_dec_nr_pmds(mm); no_pmd: pud_free(mm, new_pud); no_pud: @@ -130,9 +131,11 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd_base) pte = pmd_pgtable(*pmd); pmd_clear(pmd); pte_free(mm, pte); + atomic_long_dec(&mm->nr_ptes); no_pmd: pud_clear(pud); pmd_free(mm, pmd); + mm_dec_nr_pmds(mm); no_pud: pgd_clear(pgd); pud_free(mm, pud); @@ -152,6 +155,7 @@ no_pgd: pmd = pmd_offset(pud, 0); pud_clear(pud); pmd_free(mm, pmd); + mm_dec_nr_pmds(mm); pgd_clear(pgd); pud_free(mm, pud); } diff --git a/arch/unicore32/mm/pgd.c b/arch/unicore32/mm/pgd.c index 08b8d4295e70..1bc00d0305d4 100644 --- a/arch/unicore32/mm/pgd.c +++ b/arch/unicore32/mm/pgd.c @@ -69,6 +69,7 @@ pgd_t *get_pgd_slow(struct mm_struct *mm) no_pte: pmd_free(mm, new_pmd); + mm_dec_nr_pmds(mm); no_pmd: free_pages((unsigned long)new_pgd, 0); no_pgd: @@ -96,7 +97,9 @@ void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd) pte = pmd_pgtable(*pmd); pmd_clear(pmd); pte_free(mm, pte); + atomic_long_dec(&mm->nr_ptes); pmd_free(mm, pmd); + mm_dec_nr_pmds(mm) free: free_pages((unsigned long) pgd, 0); } diff --git a/kernel/fork.c b/kernel/fork.c index c99098c52641..76d6f292274c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -606,6 +606,14 @@ static void check_mm(struct mm_struct *mm) printk(KERN_ALERT "BUG: Bad rss-counter state " "mm:%p idx:%d val:%ld\n", mm, i, x); } + + if (atomic_long_read(&mm->nr_ptes)) + pr_alert("BUG: non-zero nr_ptes on freeing mm: %ld", + atomic_long_read(&mm->nr_ptes)); + if (mm_nr_pmds(mm)) + pr_alert("BUG: non-zero nr_pmds on freeing mm: %ld", + mm_nr_pmds(mm)); + #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS VM_BUG_ON_MM(mm->pmd_huge_pte, mm); #endif diff --git a/mm/mmap.c b/mm/mmap.c index 6a7d36d133fb..c5f44682c0d1 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2851,11 +2851,6 @@ void exit_mmap(struct mm_struct *mm) vma = remove_vma(vma); } vm_unacct_memory(nr_accounted); - - WARN_ON(atomic_long_read(&mm->nr_ptes) > - round_up(FIRST_USER_ADDRESS, PMD_SIZE) >> PMD_SHIFT); - WARN_ON(mm_nr_pmds(mm) > - round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT); } /* Insert vm structure into process list sorted by address