Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933442AbdCaLYh (ORCPT ); Fri, 31 Mar 2017 07:24:37 -0400 Received: from mail-oi0-f68.google.com ([209.85.218.68]:33848 "EHLO mail-oi0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933040AbdCaLYF (ORCPT ); Fri, 31 Mar 2017 07:24:05 -0400 MIME-Version: 1.0 In-Reply-To: <87mvc13fk1.fsf@intel.com> References: <20170330094627.29460-1-jslaby@suse.cz> <20170331072148.lbb7x6tj5egkpppm@zhen-hp.sh.intel.com> <87mvc13fk1.fsf@intel.com> From: Arnd Bergmann Date: Fri, 31 Mar 2017 13:23:58 +0200 X-Google-Sender-Auth: toC64ohp1EVWoDPtct9RbeDQ8MI Message-ID: Subject: Re: [PATCH] drm/i915: disable KASAN for handlers To: Jani Nikula Cc: Zhenyu Wang , Jiri Slaby , Linux Kernel Mailing List , Martin Liska , Zhi Wang , Daniel Vetter , David Airlie , intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, dri-devel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2668 Lines: 63 On Fri, Mar 31, 2017 at 12:29 PM, Jani Nikula wrote: > On Fri, 31 Mar 2017, Zhenyu Wang wrote: >> On 2017.03.30 11:46:27 +0200, Jiri Slaby wrote: >>> Handlers are currently the only blocker to compile the kernel with gcc 7 >>> and KASAN+use-after-scope enabled: >>> drivers/gpu/drm/i915/gvt/handlers.c:2200:1: error: the frame size of 43760 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] >>> drivers/gpu/drm/i915/gvt/handlers.c:2402:1: error: the frame size of 9400 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] >>> drivers/gpu/drm/i915/gvt/handlers.c:2628:1: error: the frame size of 11256 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] >>> >>> It is due to many expansions of MMIO_* macros in init_generic_mmio_info. >>> INTEL_GVT_MMIO_OFFSET generates for each such line a __reg and an >>> offset. There are too many for KASAN to keep up. >>> >>> So disable KASAN for this file. >>> >>> Signed-off-by: Jiri Slaby >>> Cc: Martin Liska >>> Cc: Zhenyu Wang >>> Cc: Zhi Wang >>> Cc: Daniel Vetter >>> Cc: Jani Nikula >>> Cc: David Airlie >>> Cc: intel-gvt-dev@lists.freedesktop.org >>> Cc: intel-gfx@lists.freedesktop.org >>> Cc: dri-devel@lists.freedesktop.org >>> --- >>> drivers/gpu/drm/i915/gvt/Makefile | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/drivers/gpu/drm/i915/gvt/Makefile b/drivers/gpu/drm/i915/gvt/Makefile >>> index b123c20e2097..942f1849d194 100644 >>> --- a/drivers/gpu/drm/i915/gvt/Makefile >>> +++ b/drivers/gpu/drm/i915/gvt/Makefile >>> @@ -6,3 +6,5 @@ GVT_SOURCE := gvt.o aperture_gm.o handlers.o vgpu.o trace_points.o firmware.o \ >>> ccflags-y += -I$(src) -I$(src)/$(GVT_DIR) -Wall >>> i915-y += $(addprefix $(GVT_DIR)/, $(GVT_SOURCE)) >>> obj-$(CONFIG_DRM_I915_GVT_KVMGT) += $(GVT_DIR)/kvmgt.o >>> + >>> +KASAN_SANITIZE_handlers.o := n >>> -- >>> 2.12.2 >>> >> >> Applied this, we'd better cleanup legacy usage to current i915 mmio >> reg define. Thanks! > > Hmmh, that was a bit fast, there was a related discussion going in [1]. > > BR, > Jani. > > > [1] http://mid.mail-archive.com/20170320215713.3086140-1-arnd@arndb.de Sorry about that, it looked like I never replied to your last mail. There is also a related problem that I had sent another fix for: https://patchwork.kernel.org/patch/9601349/ I still think that my two patches are correct and they should both be applied. Arnd