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 3B92BC46467 for ; Wed, 4 Jan 2023 10:24:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234368AbjADKYx (ORCPT ); Wed, 4 Jan 2023 05:24:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234001AbjADKYs (ORCPT ); Wed, 4 Jan 2023 05:24:48 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B2931AA08 for ; Wed, 4 Jan 2023 02:24:47 -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 32E176164B for ; Wed, 4 Jan 2023 10:24:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31511C433EF; Wed, 4 Jan 2023 10:24:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672827886; bh=YJDznZgeh+BEyxpBFvqDWK88sgorfwfW6T+7n5G8kBk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lgVGP5VVq0BrTBujIIWDYrh7WrFCLSxLy5waJh/0bBcp5l+kzsA6nWg4S2HxA4HeC YVdIEqt2xlij1Cjr3kBA7ehjmrNQsYSOtHz9m9GHdYtCDz+eXm0TmqhnNglyOQLq7c xxVcOXghk5cQlUk1akUMA+uf6y53euoquLn1xVbz8Tit+zEq6XvRV+WxwJtjHmJVmi R68APvlnk4Wn7xgAdZb8tHCQA/NBPC4KQpT0DRz4uL+vny2B7Yz79pXk6FVoV1R0qz albb58E8tcADOMab4FANw7CsHsKm+Vq67aCfROpBiPxgHfd4TC6BsLAG3BC447ILmK GR0gWL1KKtAJQ== Date: Wed, 4 Jan 2023 12:24:34 +0200 From: Mike Rapoport To: Levi Yun Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [PATCH] memblock: Fix return sizeless candidate on __memblock_find_range_top_down. Message-ID: References: <20230104095049.59043-1-ppbuk5246@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230104095049.59043-1-ppbuk5246@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 04, 2023 at 06:50:49PM +0900, Levi Yun wrote: > __memblock_find_range_top_down can return start address of free region > which sizeless then user speicified. > To prevent the above case, add size check on candidate free region. Did you see an actual issue or it's solely based on code inspection? > Signed-off-by: Levi Yun > --- > mm/memblock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/memblock.c b/mm/memblock.c > index 511d4783dcf1..710e2ef8d67d 100644 > --- a/mm/memblock.c > +++ b/mm/memblock.c > @@ -262,7 +262,7 @@ __memblock_find_range_top_down(phys_addr_t start, phys_addr_t end, > continue; > > cand = round_down(this_end - size, align); > - if (cand >= this_start) > + if (cand >= this_start && this_end - cand >= size) > return cand; > } > > -- > 2.35.1 > -- Sincerely yours, Mike.