Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752547AbbEGOTg (ORCPT ); Thu, 7 May 2015 10:19:36 -0400 Received: from mail-wg0-f41.google.com ([74.125.82.41]:33409 "EHLO mail-wg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752084AbbEGOP7 (ORCPT ); Thu, 7 May 2015 10:15:59 -0400 From: Robert Bragg To: intel-gfx@lists.freedesktop.org Cc: Daniel Vetter , Jani Nikula , David Airlie , Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-api@vger.kernel.org Subject: [RFC PATCH 02/11] perf: Add PERF_PMU_CAP_IS_DEVICE flag Date: Thu, 7 May 2015 15:15:45 +0100 Message-Id: <1431008154-6833-3-git-send-email-robert@sixbynine.org> X-Mailer: git-send-email 2.3.2 In-Reply-To: <1431008154-6833-1-git-send-email-robert@sixbynine.org> References: <1431008154-6833-1-git-send-email-robert@sixbynine.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3017 Lines: 95 The PERF_PMU_CAP_IS_DEVICE flag provides pmu drivers a way to declare that they only monitor device specific metrics and since they don't monitor any cpu metrics then perf should bypass any cpu centric security checks, as well as disallow cpu centric attributes. Signed-off-by: Robert Bragg --- include/linux/perf_event.h | 1 + kernel/events/core.c | 39 +++++++++++++++++++++++++++++++++------ 2 files changed, 34 insertions(+), 6 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 2b62198..1af35b4 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -166,6 +166,7 @@ struct perf_event; * pmu::capabilities flags */ #define PERF_PMU_CAP_NO_INTERRUPT 0x01 +#define PERF_PMU_CAP_IS_DEVICE 0x02 /** * struct pmu - generic performance monitoring unit diff --git a/kernel/events/core.c b/kernel/events/core.c index 38c240c..7218b01 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3330,7 +3330,8 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) if (!task) { /* Must be root to operate on a CPU event: */ - if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) + if (!(pmu->capabilities & PERF_PMU_CAP_IS_DEVICE) && + perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); /* @@ -7475,11 +7476,6 @@ SYSCALL_DEFINE5(perf_event_open, if (err) return err; - if (!attr.exclude_kernel) { - if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; - } - if (attr.freq) { if (attr.sample_freq > sysctl_perf_event_sample_rate) return -EINVAL; @@ -7538,6 +7534,37 @@ SYSCALL_DEFINE5(perf_event_open, goto err_cpus; } + if (event->pmu->capabilities & PERF_PMU_CAP_IS_DEVICE) { + + /* Don't allow cpu centric attributes... */ + if (event->attr.exclude_user || + event->attr.exclude_callchain_user || + event->attr.exclude_kernel || + event->attr.exclude_callchain_kernel || + event->attr.exclude_hv || + event->attr.exclude_idle || + event->attr.exclude_host || + event->attr.exclude_guest || + event->attr.mmap || + event->attr.comm || + event->attr.task) + return -EINVAL; + + if (attr.sample_type & + (PERF_SAMPLE_IP | + PERF_SAMPLE_TID | + PERF_SAMPLE_ADDR | + PERF_SAMPLE_CALLCHAIN | + PERF_SAMPLE_CPU | + PERF_SAMPLE_BRANCH_STACK | + PERF_SAMPLE_REGS_USER | + PERF_SAMPLE_STACK_USER)) + return -EINVAL; + } else if (!attr.exclude_kernel) { + if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) + return -EACCES; + } + if (flags & PERF_FLAG_PID_CGROUP) { err = perf_cgroup_connect(pid, event, &attr, group_leader); if (err) { -- 2.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/