From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:42696 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740AbeA2NKf (ORCPT ); Mon, 29 Jan 2018 08:10:35 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiao Liang , Thomas Gleixner Subject: [PATCH 4.14 60/71] perf/x86/amd/power: Do not load AMD power module on !AMD platforms Date: Mon, 29 Jan 2018 13:57:28 +0100 Message-Id: <20180129123831.617525907@linuxfoundation.org> In-Reply-To: <20180129123827.271171825@linuxfoundation.org> References: <20180129123827.271171825@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xiao Liang commit 40d4071ce2d20840d224b4a77b5dc6f752c9ab15 upstream. The AMD power module can be loaded on non AMD platforms, but unload fails with the following Oops: BUG: unable to handle kernel NULL pointer dereference at (null) IP: __list_del_entry_valid+0x29/0x90 Call Trace: perf_pmu_unregister+0x25/0xf0 amd_power_pmu_exit+0x1c/0xd23 [power] SyS_delete_module+0x1a8/0x2b0 ? exit_to_usermode_loop+0x8f/0xb0 entry_SYSCALL_64_fastpath+0x20/0x83 Return -ENODEV instead of 0 from the module init function if the CPU does not match. Fixes: c7ab62bfbe0e ("perf/x86/amd/power: Add AMD accumulated power reporting mechanism") Signed-off-by: Xiao Liang Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20180122061252.6394-1-xiliang@redhat.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/events/amd/power.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/events/amd/power.c +++ b/arch/x86/events/amd/power.c @@ -277,7 +277,7 @@ static int __init amd_power_pmu_init(voi int ret; if (!x86_match_cpu(cpu_match)) - return 0; + return -ENODEV; if (!boot_cpu_has(X86_FEATURE_ACC_POWER)) return -ENODEV;