From patchwork Wed Jun 19 05:08:41 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Ghiti X-Patchwork-Id: 11003395 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 12711186E for ; Wed, 19 Jun 2019 05:15:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 036FF28B4C for ; Wed, 19 Jun 2019 05:15:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E676128B4D; Wed, 19 Jun 2019 05:15:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9457628B4D for ; Wed, 19 Jun 2019 05:15:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730555AbfFSFPF (ORCPT ); Wed, 19 Jun 2019 01:15:05 -0400 Received: from relay3-d.mail.gandi.net ([217.70.183.195]:48277 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725854AbfFSFPE (ORCPT ); Wed, 19 Jun 2019 01:15:04 -0400 X-Originating-IP: 79.86.19.127 Received: from alex.numericable.fr (127.19.86.79.rev.sfr.net [79.86.19.127]) (Authenticated sender: alex@ghiti.fr) by relay3-d.mail.gandi.net (Postfix) with ESMTPSA id E2FD860012; Wed, 19 Jun 2019 05:14:58 +0000 (UTC) From: Alexandre Ghiti To: Andrew Morton Cc: "James E . J . Bottomley" , Helge Deller , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Yoshinori Sato , Rich Felker , "David S . Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Dave Hansen , Andy Lutomirski , Peter Zijlstra , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, Alexandre Ghiti Subject: [PATCH 5/8] mm: Start fallback top-down mmap at mm->mmap_base Date: Wed, 19 Jun 2019 01:08:41 -0400 Message-Id: <20190619050844.5294-6-alex@ghiti.fr> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190619050844.5294-1-alex@ghiti.fr> References: <20190619050844.5294-1-alex@ghiti.fr> MIME-Version: 1.0 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In case of mmap failure in top-down mode, there is no need to go through the whole address space again for the bottom-up fallback: the goal of this fallback is to find, as a last resort, space between the top-down mmap base and the stack, which is the only place not covered by the top-down mmap. Signed-off-by: Alexandre Ghiti --- mm/mmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mmap.c b/mm/mmap.c index dedae10cb6e2..e563145c1ff4 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2185,7 +2185,7 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, if (offset_in_page(addr)) { VM_BUG_ON(addr != -ENOMEM); info.flags = 0; - info.low_limit = TASK_UNMAPPED_BASE; + info.low_limit = arch_get_mmap_base(addr, mm->mmap_base); info.high_limit = mmap_end; addr = vm_unmapped_area(&info); }