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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT 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 55A51C004C9 for ; Tue, 7 May 2019 05:51:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2790C204FD for ; Tue, 7 May 2019 05:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557208313; bh=/PXPE8j4QrWpIB45+kYwvSBrtZU8uMuCh26U6b8XGiU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Hj+I7sBFXITNhRPxjeqQde1banYzFL56jMZpi3+tKqZ4WdyiHCLL/2vQMAlnuOkdK Joe/QuMtOs6AilQ4Trw3c+X1V4pUCBrqmrUmDcbgVP+8Osx3o5c5+DLLweifAymKQz QGARwkDFC5vb4z99jIqxfL4QMa6fvNNj2gQQMB3Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727985AbfEGFvr (ORCPT ); Tue, 7 May 2019 01:51:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:59304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728929AbfEGFjr (ORCPT ); Tue, 7 May 2019 01:39:47 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4E98A20578; Tue, 7 May 2019 05:39:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557207586; bh=/PXPE8j4QrWpIB45+kYwvSBrtZU8uMuCh26U6b8XGiU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tGIqxbIAOZIzJKAvileGS0Ytyr6dFlSaA8AWqJ7ZLn8BlyAWp5GwfjE6GAV2rprcN Gg4Rl4TN/cN5i6Rd42sqbzPb43+XWV8+c39tCkfPHu6hsPA6Z1awKC4BVhFfhPCEx9 slFjGDbzAP9dmu9sBN6CBOlIxjcxDyA91WjmyPjc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Huacai Chen , Paul Burton , Ralf Baechle , James Hogan , linux-mips@linux-mips.org, Fuxin Zhang , Zhangjin Wu , Huacai Chen , Sasha Levin , linux-mips@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 37/95] MIPS: VDSO: Reduce VDSO_RANDOMIZE_SIZE to 64MB for 64bit Date: Tue, 7 May 2019 01:37:26 -0400 Message-Id: <20190507053826.31622-37-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190507053826.31622-1-sashal@kernel.org> References: <20190507053826.31622-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Huacai Chen [ Upstream commit c61c7def1fa0a722610d89790e0255b74f3c07dd ] Commit ea7e0480a4b6 ("MIPS: VDSO: Always map near top of user memory") set VDSO_RANDOMIZE_SIZE to 256MB for 64bit kernel. But take a look at arch/mips/mm/mmap.c we can see that MIN_GAP is 128MB, which means the mmap_base may be at (user_address_top - 128MB). This make the stack be surrounded by mmaped areas, then stack expanding fails and causes a segmentation fault. Therefore, VDSO_RANDOMIZE_SIZE should be less than MIN_GAP and this patch reduce it to 64MB. Signed-off-by: Huacai Chen Signed-off-by: Paul Burton Fixes: ea7e0480a4b6 ("MIPS: VDSO: Always map near top of user memory") Patchwork: https://patchwork.linux-mips.org/patch/20910/ Cc: Ralf Baechle Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: Fuxin Zhang Cc: Zhangjin Wu Cc: Huacai Chen Signed-off-by: Sasha Levin --- arch/mips/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index 8bbbab611a3f..0b86a01de956 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -81,7 +81,7 @@ extern unsigned int vced_count, vcei_count; #endif -#define VDSO_RANDOMIZE_SIZE (TASK_IS_32BIT_ADDR ? SZ_1M : SZ_256M) +#define VDSO_RANDOMIZE_SIZE (TASK_IS_32BIT_ADDR ? SZ_1M : SZ_64M) extern unsigned long mips_stack_top(void); #define STACK_TOP mips_stack_top() -- 2.20.1