From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752072AbcAEKLg (ORCPT ); Tue, 5 Jan 2016 05:11:36 -0500 Received: from foss.arm.com ([217.140.101.70]:57268 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751472AbcAEKKe (ORCPT ); Tue, 5 Jan 2016 05:10:34 -0500 Date: Tue, 5 Jan 2016 10:10:19 +0000 From: Catalin Marinas To: zhongjiang Cc: "linux-kernel@vger.kernel.org" , "ryabinin.a.a@gmail.com" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "qiuxishi@huawei.com" , "long.wanglong@huawei.com" , Will Deacon Subject: Re: [PATCH] arm64: fix add kasan bug Message-ID: <20160105101017.GA14545@localhost.localdomain> References: <1451556549-8962-1-git-send-email-zhongjiang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1451556549-8962-1-git-send-email-zhongjiang@huawei.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 31, 2015 at 10:09:09AM +0000, zhongjiang wrote: > From: zhong jiang > > In general, each process have 16kb stack space to use, but > stack need extra space to store red_zone when kasan enable. > the patch fix above question. > > Signed-off-by: zhong jiang > --- > arch/arm64/include/asm/thread_info.h | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h > index 90c7ff2..45b5a7e 100644 > --- a/arch/arm64/include/asm/thread_info.h > +++ b/arch/arm64/include/asm/thread_info.h [...] > +#ifdef CONFIG_KASAN > +#define THREAD_SIZE 32768 > +#else > #define THREAD_SIZE 16384 > +#endif I'm not really keen on increasing the stack size to 32KB when KASan is enabled (that's 8 4K pages). Have you actually seen a real problem with the default size? How large is the red_zone? With 4.5 we are going for separate IRQ stack on arm64, so the typical stack overflow case no longer exists. -- Catalin