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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 839D0C7EE45 for ; Fri, 9 Jun 2023 15:22:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241365AbjFIPWb (ORCPT ); Fri, 9 Jun 2023 11:22:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231938AbjFIPW1 (ORCPT ); Fri, 9 Jun 2023 11:22:27 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18B1330F7 for ; Fri, 9 Jun 2023 08:22:24 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1686324143; 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=1naFavr92GwX5FkOX7e/quHSVxFZtV+4DxcoRTFPC6Q=; b=UIfNsraeML09qxs86FX0zo6kBEbq1ALHAB85lj3ub1Z7X9LgnQy93k9XHTm/vilJEXs5Ir llkKGj8FcmXONuq8zMP/hVC7hFa5CU+vP4szIJ++CqYUg0oG55tj3d8S+22215iQtMenKP poQQCPOTBC2aU4N8SMoqmm81WBs542fnlCwbxiCLusR4bmhTo8oC87hUE+ThnFcD6cVPS3 n15LHd2SAbV+7UcxCJANo2DuWyNab0EXt6fvcDmOuHWK18eeATLenM8Ec8qFzuz//j2u/9 E75T7FSAqevWkJt0ON7ECFZADEA5vloKe26pANHLIPTCYQE+ZxjzSB6XGAFZPA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1686324143; 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=1naFavr92GwX5FkOX7e/quHSVxFZtV+4DxcoRTFPC6Q=; b=ZzrSBncpCwezVe7wuseibyrYIlve0G2tEZyR0dnz2li0uUYOkSVjSxUhDMo+YnwSiUwc5V jV4R5S8a5JJ7roAA== To: Nikolay Borisov , x86@kernel.org Cc: linux-kernel@vger.kernel.org, mhocko@suse.com, jslaby@suse.cz, Nikolay Borisov Subject: Re: [PATCH v2 3/4] x86/entry: Disable IA32 syscall if ia32_disabled is true In-Reply-To: <20230609111311.4110901-4-nik.borisov@suse.com> References: <20230609111311.4110901-1-nik.borisov@suse.com> <20230609111311.4110901-4-nik.borisov@suse.com> Date: Fri, 09 Jun 2023 17:22:22 +0200 Message-ID: <87edmkirtd.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 09 2023 at 14:13, Nikolay Borisov wrote: > First stage of disabling ia32 compat layer is to disable 32bit syscall > entry points. Legacy int 0x80 vector is disabled by zeroing out its gate > descriptor in the idt and the sysenter vector is disabled by re-using > the existing code in case IA32_EMULATION is disabled. This describes WHAT the patch does without providing any context. > + if ((IS_ENABLED(CONFIG_IA32_EMULATION) && ia32_disabled) || > + !IS_ENABLED(CONFIG_IA32_EMULATION)) { I told you before that my brain based compiler complains about your patches not building with CONFIG_IA32_EMULATION=n. The above still fails to build. Aside of that this condition is convoluted and can be simplified to exactly a simple and understandable if (foo) which is actually the obvious solution to make it compile in all configurations. It's not too much asked to flip the config switch which affects the code you are changing for a test. > @@ -226,6 +226,13 @@ void __init idt_setup_early_traps(void) > void __init idt_setup_traps(void) > { > idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts), true); > + > + if (IS_ENABLED(CONFIG_IA32_EMULATION) && ia32_disabled) { Ditto. > + gate_desc null_desc = {}; Lacks a newline between declaration and code. It's documented to be required, no? > + write_idt_entry(idt_table, IA32_SYSCALL_VECTOR, &null_desc); > + clear_bit(IA32_SYSCALL_VECTOR, system_vectors); > + } That aside, I asked you to split IA32_SYSCALL_VECTOR out of def_idts[] and handle it separately, no? If you disagree with me then reply to my review first instead of ignoring me silently. I don't care about you wasting your time, but I very much care about you wasting my time. Stop this right now before it becomes a habit. Thanks, tglx