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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA100C32793 for ; Wed, 18 Jan 2023 21:40:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230125AbjARVk0 (ORCPT ); Wed, 18 Jan 2023 16:40:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231249AbjARVkY (ORCPT ); Wed, 18 Jan 2023 16:40:24 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C2663C24 for ; Wed, 18 Jan 2023 13:40:23 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0A46B61A53 for ; Wed, 18 Jan 2023 21:40:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 65831C433F0; Wed, 18 Jan 2023 21:40:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1674078022; bh=4BSkVUpJfgOB5c2fAmUXm2lpAVHDxXNy7DmXp2S+vpo=; h=Date:To:From:Subject:From; b=QBQHddB7EZvuXawn3IT7W6BkiBuGrq57NlVLtDXyKzdv3rJOG1S5qCq41dNogIygf Z/9s22KUyW1Rlocv3dgEE26qQZPcZoBzA+FdA7QYtfERgGQ79oj3OaPCZ6UFMeDx4i B75tcgwgDc2K6gnAF6tsYGbpgVLwc2AebwapKZGM= Date: Wed, 18 Jan 2023 13:40:21 -0800 To: mm-commits@vger.kernel.org, m.szyprowski@samsung.com, minchan@kernel.org, laurent.pinchart@ideasonboard.com, iamjoonsoo.kim@lge.com, ppbuk5246@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-cma-fix-potential-memory-loss-on-cma_declare_contiguous_nid.patch added to mm-unstable branch Message-Id: <20230118214022.65831C433F0@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/cma: fix potential memory loss on cma_declare_contiguous_nid has been added to the -mm mm-unstable branch. Its filename is mm-cma-fix-potential-memory-loss-on-cma_declare_contiguous_nid.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-cma-fix-potential-memory-loss-on-cma_declare_contiguous_nid.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Levi Yun Subject: mm/cma: fix potential memory loss on cma_declare_contiguous_nid Date: Wed, 18 Jan 2023 17:05:23 +0900 Suppose memblock_alloc_range_nid() with highmem_start succeeds when cma_declare_contiguous_nid is called with !fixed on a 32-bit system with PHYS_ADDR_T_64BIT enabled with memblock.bottom_up == false. But the next trial to memblock_alloc_range_nid() to allocate in [SIZE_4G, limits) nullifies former successfully allocated addr and it retries memblock_alloc_ragne_nid(). In this situation, the first successfully allocated address area is lost. Change the order of allocation (SIZE_4G, high_memory and base) and check whether the allocated succeeded to prevent potential memory loss. Link: https://lkml.kernel.org/r/20230118080523.44522-1-ppbuk5246@gmail.com Signed-off-by: Levi Yun Cc: Laurent Pinchart Cc: Marek Szyprowski Cc: Joonsoo Kim Cc: Minchan Kim Signed-off-by: Andrew Morton --- mm/cma.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) --- a/mm/cma.c~mm-cma-fix-potential-memory-loss-on-cma_declare_contiguous_nid +++ a/mm/cma.c @@ -331,18 +331,6 @@ int __init cma_declare_contiguous_nid(ph phys_addr_t addr = 0; /* - * All pages in the reserved area must come from the same zone. - * If the requested region crosses the low/high memory boundary, - * try allocating from high memory first and fall back to low - * memory in case of failure. - */ - if (base < highmem_start && limit > highmem_start) { - addr = memblock_alloc_range_nid(size, alignment, - highmem_start, limit, nid, true); - limit = highmem_start; - } - - /* * If there is enough memory, try a bottom-up allocation first. * It will place the new cma area close to the start of the node * and guarantee that the compaction is moving pages out of the @@ -359,6 +347,18 @@ int __init cma_declare_contiguous_nid(ph } #endif + /* + * All pages in the reserved area must come from the same zone. + * If the requested region crosses the low/high memory boundary, + * try allocating from high memory first and fall back to low + * memory in case of failure. + */ + if (!addr && base < highmem_start && limit > highmem_start) { + addr = memblock_alloc_range_nid(size, alignment, + highmem_start, limit, nid, true); + limit = highmem_start; + } + if (!addr) { addr = memblock_alloc_range_nid(size, alignment, base, limit, nid, true); _ Patches currently in -mm which might be from ppbuk5246@gmail.com are mm-cma-fix-potential-memory-loss-on-cma_declare_contiguous_nid.patch