From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754802AbcFPRNz (ORCPT ); Thu, 16 Jun 2016 13:13:55 -0400 Received: from mail.skyhub.de ([78.46.96.112]:55363 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753899AbcFPRNx (ORCPT ); Thu, 16 Jun 2016 13:13:53 -0400 From: Borislav Petkov To: Ingo Molnar Cc: Tony Battersby , LKML Subject: [PATCH 1/2] x86/amd_nb: Return negative value when no northbridges Date: Thu, 16 Jun 2016 19:13:49 +0200 Message-Id: <1466097230-5333-2-git-send-email-bp@alien8.de> X-Mailer: git-send-email 2.7.3 In-Reply-To: <1466097230-5333-1-git-send-email-bp@alien8.de> References: <1466097230-5333-1-git-send-email-bp@alien8.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov AMD northbridges users call amd_cache_northbridges() and it returns a negative value to signal that we weren't able to cache/detect any northbridges on the system. At least, it should do so as all its callers expect it to do so. But it does return a negative value only when kmalloc fails. Fix it to return -ENODEV if there are no NBs cached as otherwise, amd_nb users like amd64_edac, for example, which relies on it to know whether it should load or not, gets loaded on systems like Intel Xeons where it shouldn't. Reported-and-tested-by: Tony Battersby Signed-off-by: Borislav Petkov Cc: Link: https://lkml.kernel.org/r/5761BEB0.9000807@cybernetics.com --- arch/x86/kernel/amd_nb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c index a147e676fc7b..e991d5c8bb3a 100644 --- a/arch/x86/kernel/amd_nb.c +++ b/arch/x86/kernel/amd_nb.c @@ -71,8 +71,8 @@ int amd_cache_northbridges(void) while ((misc = next_northbridge(misc, amd_nb_misc_ids)) != NULL) i++; - if (i == 0) - return 0; + if (!i) + return -ENODEV; nb = kzalloc(i * sizeof(struct amd_northbridge), GFP_KERNEL); if (!nb) -- 2.7.3