From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965415Ab2I1TgY (ORCPT ); Fri, 28 Sep 2012 15:36:24 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:51579 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965353Ab2I1TAf (ORCPT ); Fri, 28 Sep 2012 15:00:35 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg KH , alan@lxorguk.ukuu.org.uk, Robert Richter , Peter Zijlstra , Ingo Molnar Subject: [ 136/262] perf/x86/ibs: Check syscall attribute flags Date: Fri, 28 Sep 2012 11:51:05 -0700 Message-Id: <20120928183014.071305234@linuxfoundation.org> X-Mailer: git-send-email 1.7.10.1.362.g242cab3 In-Reply-To: <20120928182957.993484211@linuxfoundation.org> References: <20120928182957.993484211@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg KH 3.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Robert Richter commit bad9ac2d7f878a31cf1ae8c1ee3768077d222bcb upstream. Current implementation simply ignores attribute flags. Thus, there is no notification to userland of unsupported features. Check syscall's attribute flags to let userland know if a feature is supported by the kernel. This is also needed to distinguish between future kernels what might support a feature. Signed-off-by: Robert Richter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20120910093018.GO8285@erda.amd.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/perf_event_amd_ibs.c | 12 ++++++++++++ include/linux/perf_event.h | 2 ++ 2 files changed, 14 insertions(+) --- a/arch/x86/kernel/cpu/perf_event_amd_ibs.c +++ b/arch/x86/kernel/cpu/perf_event_amd_ibs.c @@ -207,6 +207,15 @@ static int perf_ibs_precise_event(struct return -EOPNOTSUPP; } +static const struct perf_event_attr ibs_notsupp = { + .exclude_user = 1, + .exclude_kernel = 1, + .exclude_hv = 1, + .exclude_idle = 1, + .exclude_host = 1, + .exclude_guest = 1, +}; + static int perf_ibs_init(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; @@ -227,6 +236,9 @@ static int perf_ibs_init(struct perf_eve if (event->pmu != &perf_ibs->pmu) return -ENOENT; + if (perf_flags(&event->attr) & perf_flags(&ibs_notsupp)) + return -EINVAL; + if (config & ~perf_ibs->config_mask) return -EINVAL; --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -274,6 +274,8 @@ struct perf_event_attr { __u64 branch_sample_type; /* enum branch_sample_type */ }; +#define perf_flags(attr) (*(&(attr)->read_format + 1)) + /* * Ioctls that can be done on a perf event fd: */