From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934669AbeEILp1 (ORCPT ); Wed, 9 May 2018 07:45:27 -0400 Received: from mga14.intel.com ([192.55.52.115]:26332 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934376AbeEILpY (ORCPT ); Wed, 9 May 2018 07:45:24 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,381,1520924400"; d="scan'208";a="54445900" From: Adrian Hunter To: Thomas Gleixner , Arnaldo Carvalho de Melo Cc: Ingo Molnar , Peter Zijlstra , Andy Lutomirski , "H. Peter Anvin" , Andi Kleen , Alexander Shishkin , Dave Hansen , Joerg Roedel , Jiri Olsa , linux-kernel@vger.kernel.org, x86@kernel.org Subject: [PATCH RFC 06/19] perf tools: Fix kernel_start for KPTI on x86_64 Date: Wed, 9 May 2018 14:43:35 +0300 Message-Id: <1525866228-30321-7-git-send-email-adrian.hunter@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1525866228-30321-1-git-send-email-adrian.hunter@intel.com> References: <1525866228-30321-1-git-send-email-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On x86_64, KPTI entry trampolines are less than the start of kernel text, but still above 2^63. So leave kernel_start = 1ULL << 63 for x86_64. Signed-off-by: Adrian Hunter --- tools/perf/util/machine.c | 16 +++++++++++++++- tools/perf/util/machine.h | 2 ++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 72a351613d85..22047ff3cf2a 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2296,6 +2296,15 @@ int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid, return 0; } +/* + * Compares the raw arch string. N.B. see instead perf_env__arch() if a + * normalized arch is needed. + */ +bool machine__is(struct machine *machine, const char *arch) +{ + return machine->env && !strcmp(machine->env->arch, arch); +} + int machine__get_kernel_start(struct machine *machine) { struct map *map = machine__kernel_map(machine); @@ -2312,7 +2321,12 @@ int machine__get_kernel_start(struct machine *machine) machine->kernel_start = 1ULL << 63; if (map) { err = map__load(map); - if (!err) + /* + * On x86_64, KPTI entry trampolines are less than the + * start of kernel text, but still above 2^63. So leave + * kernel_start = 1ULL << 63 for x86_64. + */ + if (!err && !machine__is(machine, "x86_64")) machine->kernel_start = map->start; } return err; diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index 388fb4741c54..b31d33b5aa2a 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -188,6 +188,8 @@ static inline bool machine__is_host(struct machine *machine) return machine ? machine->pid == HOST_KERNEL_ID : false; } +bool machine__is(struct machine *machine, const char *arch); + struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid); struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid); -- 1.9.1