From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f50.google.com (mail-wm0-f50.google.com [74.125.82.50]) by kanga.kvack.org (Postfix) with ESMTP id 6DB766B0261 for ; Sun, 7 Feb 2016 15:54:12 -0500 (EST) Received: by mail-wm0-f50.google.com with SMTP id r129so90080167wmr.0 for ; Sun, 07 Feb 2016 12:54:12 -0800 (PST) Received: from radon.swed.at (a.ns.miles-group.at. [95.130.255.143]) by mx.google.com with ESMTPS id l187si12580251wmf.83.2016.02.07.12.54.11 for (version=TLS1 cipher=AES128-SHA bits=128/128); Sun, 07 Feb 2016 12:54:11 -0800 (PST) Subject: Re: [PATCH v10 3/4] x86, mce: Add __mcsafe_copy() References: <6b63a88e925bbc821dc87f209909c3c1166b3261.1454618190.git.tony.luck@intel.com> <20160207165524.GF5862@pd.tnic> From: Richard Weinberger Message-ID: <56B7AEEE.5070504@nod.at> Date: Sun, 7 Feb 2016 21:54:06 +0100 MIME-Version: 1.0 In-Reply-To: <20160207165524.GF5862@pd.tnic> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Borislav Petkov , Tony Luck Cc: Ingo Molnar , Andrew Morton , Andy Lutomirski , Dan Williams , elliott@hpe.com, Brian Gerst , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@ml01.01.org, x86@kernel.org Am 07.02.2016 um 17:55 schrieb Borislav Petkov: > due to those > >> + _ASM_EXTABLE_FAULT(0b,30b) >> + _ASM_EXTABLE_FAULT(1b,31b) >> + _ASM_EXTABLE_FAULT(2b,32b) >> + _ASM_EXTABLE_FAULT(3b,33b) >> + _ASM_EXTABLE_FAULT(4b,34b) > > things below and that's because ex_handler_fault() is defined in > arch/x86/mm/extable.c and UML doesn't include that file in the build. It > takes kernel/extable.c and lib/extable.c only. > > Richi, what's the usual way to address that in UML? I.e., make an > x86-only symbol visible to the UML build too? Define a dummy one, just > so that it builds? As discussed on IRC with Boris, UML offers only minimal extable support. To get rid of the said #ifndef, UML would have to provide its own extable.c (mostly copy&paste from arch/x86) and an advanced struct exception_table_entry which includes the trap number. This implies also that UML can no longer use uaccess.h from asm-generic or has to add a new ifdef into uaccess.h to whiteout the minimal struct exception_table_entry from there. So, I'd vote to keep the #ifndef CONFIG_UML in memcpy_64.S. As soon you need another #ifndef please ping me and I'll happily bite the bullet and implement the advanced extable stuff for UML. Deal? Thanks, //richard -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org