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[2620:137:e000::1:20]) by mx.google.com with ESMTP id v7-20020aa799c7000000b0065f61db315dsi2996405pfi.204.2023.06.07.02.02.51; Wed, 07 Jun 2023 02:03:03 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linutronix.de header.s=2020 header.b="kAZd/W3Z"; dkim=neutral (no key) header.i=@linutronix.de; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=linutronix.de Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239706AbjFGI6C (ORCPT + 99 others); Wed, 7 Jun 2023 04:58:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238868AbjFGI5k (ORCPT ); Wed, 7 Jun 2023 04:57:40 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C205926AC for ; Wed, 7 Jun 2023 01:56:18 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1686128156; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=DpvU/VMM03E2+eM90PuDFm3nk7nWddaXa439gEnZ/AU=; b=kAZd/W3Zjl3r/u07MxqNf/Wu4R0A6Rb9QytM7xaOtUOTUFfvuAsEhvJN9HekERWAn+Y39p kAKhlaoL/69fzL0o+XibhxdDmJk9KRVWI4Yo0mLGqAIUu6b9tgmNzW02vYmwILNsYKcbjz ddQTGLN2EE9r6wtP1fuCXTLWKAo96BBBMBzWj1eRbtIlV3WE+NboIm5rUqNYPJ9YBCmvqE 36RnMLMTk/9IRtXLd9IQa0+5D+nxR271M1w+kOKl8MxLhk/I/8SG3YVZak9J/xMrNxjjA/ po/kr/RKWMVLiTD8QJYqWnRb6leAYACLLcdoOh2xUtxRCecfrsfbMCzja4Mu2w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1686128156; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=DpvU/VMM03E2+eM90PuDFm3nk7nWddaXa439gEnZ/AU=; b=AM1EZgtY35YffOG8PbOlVGTpWyrKhnCLIGUTjS+pycFFXJVCuG4x/HCHvl+EuD9OWBtwQf 3yM0f3S5DgjMhACA== To: Nikolay Borisov , x86@kernel.org Cc: linux-kernel@vger.kernel.org, mhocko@suse.com, jslaby@suse.cz, Nikolay Borisov Subject: Re: [PATCH 1/3] x86: Introduce ia32_disabled boot parameter In-Reply-To: <20230607072936.3766231-2-nik.borisov@suse.com> References: <20230607072936.3766231-1-nik.borisov@suse.com> <20230607072936.3766231-2-nik.borisov@suse.com> Date: Wed, 07 Jun 2023 10:55:55 +0200 Message-ID: <87r0qnk5wk.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 07 2023 at 10:29, Nikolay Borisov wrote: > Distributions would like to reduce their attack surface as much as > possible but at the same time they have to cater to a wide variety of > legacy software. One such avenue where distros have to strike a balance > is the support for 32bit syscalls on a 64bit kernel. Ideally we'd have > the ability to disable the the compat support at boot time. This would > allow the decision whether it should be disabled/enabled can be > delegated to system administrators. > > This patch simply introduces ia32_disable boot parameter which aims at https://www.kernel.org/doc/html/latest/process/maintainer-tip.html > disabling 32 bit process support even if CONFIG_IA32_EMULATION has been > selected at build time. > > Signed-off-by: Nikolay Borisov > --- > arch/x86/entry/common.c | 12 ++++++++++++ > arch/x86/include/asm/traps.h | 4 ++++ New command line parameters require documentation. https://www.kernel.org/doc/html/latest/process/ Thanks, tglx