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 8E1EAC76188 for ; Mon, 3 Apr 2023 20:36:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233355AbjDCUgv (ORCPT ); Mon, 3 Apr 2023 16:36:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231933AbjDCUgp (ORCPT ); Mon, 3 Apr 2023 16:36:45 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E71A448E for ; Mon, 3 Apr 2023 13:36:29 -0700 (PDT) Received: from zn.tnic (p5de8e687.dip0.t-ipconnect.de [93.232.230.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D9C9A1EC01A9; Mon, 3 Apr 2023 22:36:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1680554187; 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: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=dURY1xCpHXDLXAfUlVyn8rjCxWMcqqi+PH/vEcs4z5g=; b=ICr5otNGdMU0EdM8Cn5TYhOfU1Ydt/YWGbdIIhReI0kzu/52rRpi/D/kxSXXfA35D2lBj7 yx34UcFvFEgkTRbLYLEK40/zhwrtMBq6prlIXKUUeeXfKXCnOp7SjI9mEhgjON3asyB+hc euVlPMWcWWNC476TW8bMOATeRolUeyU= Date: Mon, 3 Apr 2023 22:36:23 +0200 From: Borislav Petkov To: Yazen Ghannam Cc: x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/amd_nb: Check for invalid SMN reads Message-ID: <20230403203623.GDZCs4x5yVReaPVOaS@fat_crate.local> References: <20230403164244.471141-1-yazen.ghannam@amd.com> <20230403193245.GCZCsp3RjNZFSE5f9s@fat_crate.local> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 03, 2023 at 03:40:38PM -0400, Yazen Ghannam wrote: > I don't think pci_write_config*() sets the PCI Error response like > pci_read_config(), AFAICT. diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c index 4266b64631a4..c4caade434a7 100644 --- a/arch/x86/kernel/amd_nb.c +++ b/arch/x86/kernel/amd_nb.c @@ -181,6 +181,13 @@ static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write) pr_warn("Error %s SMN address 0x%x.\n", (write ? "writing to" : "reading from"), address); + if (!write) { + if (PCI_POSSIBLE_ERROR(*value)) { + err = -ENODEV; + *value = 0; + } + } + out_unlock: mutex_unlock(&smn_mutex); -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette