From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3EB18C433DF for ; Fri, 16 Oct 2020 02:41:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BD4AE20878 for ; Fri, 16 Oct 2020 02:41:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="fn3ZPymc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD4AE20878 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4F76494000B; Thu, 15 Oct 2020 22:41:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4A828940007; Thu, 15 Oct 2020 22:41:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3959194000B; Thu, 15 Oct 2020 22:41:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0069.hostedemail.com [216.40.44.69]) by kanga.kvack.org (Postfix) with ESMTP id 0DCCD940007 for ; Thu, 15 Oct 2020 22:41:52 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id A3DB2180AD811 for ; Fri, 16 Oct 2020 02:41:51 +0000 (UTC) X-FDA: 77376238422.04.fight26_101708d27219 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin04.hostedemail.com (Postfix) with ESMTP id 8926F8002252 for ; Fri, 16 Oct 2020 02:41:51 +0000 (UTC) X-HE-Tag: fight26_101708d27219 X-Filterd-Recvd-Size: 4143 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Fri, 16 Oct 2020 02:41:51 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F09CF20FC3; Fri, 16 Oct 2020 02:41:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816110; bh=59O6rwBETi3fXBQMh7mdRlcZQ0kAc5DJljSfHMwlfKA=; h=Date:From:To:Subject:In-Reply-To:From; b=fn3ZPymck4VyR7/YUHnoYY4ywHy5w93vT5He7Qhg8VQ3gRh/iO+Ib6iTvNa0pigwy ijsrtfnh8EdddO63aBMp3VLRCTg7QX9ceKtIxSaEIfjmZsEWOPaYb/fOFLNyHo6lEv xu9fm+FCnjyDRkzu/yZJ2Mti09ssijjSbDKuNRio= Date: Thu, 15 Oct 2020 19:41:49 -0700 From: Andrew Morton To: akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, linux-mm@kvack.org, lkp@intel.com, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 015/156] mm/debug_vm_pgtable: avoid doing memory allocation with pgtable_t mapped. Message-ID: <20201016024149.3E_4VWUXO%akpm@linux-foundation.org> In-Reply-To: <20201015192732.f448da14e9854c7cb7299956@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "Aneesh Kumar K.V" Subject: mm/debug_vm_pgtable: avoid doing memory allocation with pgtable_t mapped. With highmem, pte_alloc_map() keep the level4 page table mapped using kmap_atomic(). Avoid doing new memory allocation with page table mapped like above. [ 9.409233] BUG: sleeping function called from invalid context at mm/page_alloc.c:4822 [ 9.410557] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper [ 9.411932] no locks held by swapper/1. [ 9.412595] CPU: 0 PID: 1 Comm: swapper Not tainted 5.9.0-rc3-00323-gc50eb1ed654b5 #2 [ 9.413824] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 9.415207] Call Trace: [ 9.415651] ? ___might_sleep.cold+0xa7/0xcc [ 9.416367] ? __alloc_pages_nodemask+0x14c/0x5b0 [ 9.417055] ? swap_migration_tests+0x50/0x293 [ 9.417704] ? debug_vm_pgtable+0x4bc/0x708 [ 9.418287] ? swap_migration_tests+0x293/0x293 [ 9.418911] ? do_one_initcall+0x82/0x3cb [ 9.419465] ? parse_args+0x1bd/0x280 [ 9.419983] ? rcu_read_lock_sched_held+0x36/0x60 [ 9.420673] ? trace_initcall_level+0x1f/0xf3 [ 9.421279] ? trace_initcall_level+0xbd/0xf3 [ 9.421881] ? do_basic_setup+0x9d/0xdd [ 9.422410] ? do_basic_setup+0xc3/0xdd [ 9.422938] ? kernel_init_freeable+0x72/0xa3 [ 9.423539] ? rest_init+0x134/0x134 [ 9.424055] ? kernel_init+0x5/0x12c [ 9.424574] ? ret_from_fork+0x19/0x30 Link: https://lkml.kernel.org/r/20200913110327.645310-1-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V Reported-by: kernel test robot Signed-off-by: Andrew Morton --- mm/debug_vm_pgtable.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/mm/debug_vm_pgtable.c~mm-debug_vm_pgtable-avoid-doing-memory-allocation-with-pgtable_t-mapped +++ a/mm/debug_vm_pgtable.c @@ -945,7 +945,13 @@ static int __init debug_vm_pgtable(void) p4dp = p4d_alloc(mm, pgdp, vaddr); pudp = pud_alloc(mm, p4dp, vaddr); pmdp = pmd_alloc(mm, pudp, vaddr); - ptep = pte_alloc_map(mm, pmdp, vaddr); + /* + * Allocate pgtable_t + */ + if (pte_alloc(mm, pmdp)) { + pr_err("pgtable allocation failed\n"); + return 1; + } /* * Save all the page table page addresses as the page table @@ -999,8 +1005,7 @@ static int __init debug_vm_pgtable(void) * proper page table lock. */ - ptl = pte_lockptr(mm, pmdp); - spin_lock(ptl); + ptep = pte_offset_map_lock(mm, pmdp, vaddr, &ptl); pte_clear_tests(mm, ptep, pte_aligned, vaddr, prot); pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); pte_unmap_unlock(ptep, ptl); _