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=-12.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 7392FC433DF for ; Wed, 12 Aug 2020 01:32:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3A73B20829 for ; Wed, 12 Aug 2020 01:32:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="BhvqcVoj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3A73B20829 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 D60598D000B; Tue, 11 Aug 2020 21:31:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D14978D0001; Tue, 11 Aug 2020 21:31:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB5208D000B; Tue, 11 Aug 2020 21:31:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0166.hostedemail.com [216.40.44.166]) by kanga.kvack.org (Postfix) with ESMTP id 9E9C08D0001 for ; Tue, 11 Aug 2020 21:31:59 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 76ADF180AD80F for ; Wed, 12 Aug 2020 01:31:59 +0000 (UTC) X-FDA: 77140190358.14.flock82_470061a26fe7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id 4C42418229818 for ; Wed, 12 Aug 2020 01:31:59 +0000 (UTC) X-HE-Tag: flock82_470061a26fe7 X-Filterd-Recvd-Size: 4135 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf09.hostedemail.com (Postfix) with ESMTP for ; Wed, 12 Aug 2020 01:31:58 +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 A60F9207DA; Wed, 12 Aug 2020 01:31:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597195918; bh=DOlQuN3MBpcieoHqPbvVQHLTa9MQMT8htktr790psHc=; h=Date:From:To:Subject:In-Reply-To:From; b=BhvqcVojRC6TzZFL9Re1gh91T/vi78uk4IrFHO7Sc0X/urrHn5SbfZHBsaOE6CdBX h305GjjxJz1sKGPTy+jD0HqBlGlv1lNPGVjq/DAzPjwhlg1hXXPdAAHd/k77ZCBHkv pzZix5F2sSqSJqOgkcrD9OPb1XoN7LpxAfkSrdcg= Date: Tue, 11 Aug 2020 18:31:57 -0700 From: Andrew Morton To: akpm@linux-foundation.org, guro@fb.com, linux-mm@kvack.org, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, natechancellor@gmail.com, song.bao.hua@hisilicon.com, torvalds@linux-foundation.org Subject: [patch 032/165] mm: cma: fix the name of CMA areas Message-ID: <20200812013157.V_PQIH6TB%akpm@linux-foundation.org> In-Reply-To: <20200811182949.e12ae9a472e3b5e27e16ad6c@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 4C42418229818 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 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: Barry Song Subject: mm: cma: fix the name of CMA areas Patch series "mm: fix the names of general cma and hugetlb cma", v2. The current code of CMA can only work when users pass a const string as name parameter. we need to fix the way to handle names in CMA. On the other hand, to avoid name conflicts after enabling CMA_DEBUGFS, each hugetlb should get a different CMA name. This patch (of 2): If users give a name saved in stack, the current code will generate magic pointer. if users don't give a name(NULL), kasprintf() will always return NULL as we are at the early stage. that means cma_init_reserved_mem() will return -ENOMEM if users set name parameter as NULL. [natechancellor@gmail.com: return cma->name directly in cma_get_name] Link: https://github.com/ClangBuiltLinux/linux/issues/1063 Link: http://lkml.kernel.org/r/20200623015840.621964-1-natechancellor@gmail.com Link: http://lkml.kernel.org/r/20200616223131.33828-2-song.bao.hua@hisilicon.com Signed-off-by: Barry Song Signed-off-by: Nathan Chancellor Acked-by: Roman Gushchin Reviewed-by: Mike Kravetz Signed-off-by: Andrew Morton --- mm/cma.c | 15 +++++++-------- mm/cma.h | 4 +++- 2 files changed, 10 insertions(+), 9 deletions(-) --- a/mm/cma.c~mm-cma-fix-the-name-of-cma-areas +++ a/mm/cma.c @@ -52,7 +52,7 @@ unsigned long cma_get_size(const struct const char *cma_get_name(const struct cma *cma) { - return cma->name ? cma->name : "(undefined)"; + return cma->name; } static unsigned long cma_bitmap_aligned_mask(const struct cma *cma, @@ -202,13 +202,12 @@ int __init cma_init_reserved_mem(phys_ad * subsystems (like slab allocator) are available. */ cma = &cma_areas[cma_area_count]; - if (name) { - cma->name = name; - } else { - cma->name = kasprintf(GFP_KERNEL, "cma%d\n", cma_area_count); - if (!cma->name) - return -ENOMEM; - } + + if (name) + snprintf(cma->name, CMA_MAX_NAME, name); + else + snprintf(cma->name, CMA_MAX_NAME, "cma%d\n", cma_area_count); + cma->base_pfn = PFN_DOWN(base); cma->count = size >> PAGE_SHIFT; cma->order_per_bit = order_per_bit; --- a/mm/cma.h~mm-cma-fix-the-name-of-cma-areas +++ a/mm/cma.h @@ -4,6 +4,8 @@ #include +#define CMA_MAX_NAME 64 + struct cma { unsigned long base_pfn; unsigned long count; @@ -15,7 +17,7 @@ struct cma { spinlock_t mem_head_lock; struct debugfs_u32_array dfs_bitmap; #endif - const char *name; + char name[CMA_MAX_NAME]; }; extern struct cma cma_areas[MAX_CMA_AREAS]; _