Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753582AbaGGNpf (ORCPT ); Mon, 7 Jul 2014 09:45:35 -0400 Received: from mail-we0-f169.google.com ([74.125.82.169]:56412 "EHLO mail-we0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753533AbaGGNpc (ORCPT ); Mon, 7 Jul 2014 09:45:32 -0400 From: Jean Pihet To: linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org, linux-arm-kernel@lists.infradead.org, Will Deacon Cc: Jiri Olsa , Ingo Molnar , Arnaldo Carvalho de Melo , steve.capper@linaro.org, Jean Pihet Subject: [PATCH 1/3] ARM: perf: Check that current->mm is alive before getting user callchain Date: Mon, 7 Jul 2014 15:45:08 +0200 Message-Id: <1404740710-14691-2-git-send-email-jean.pihet@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1404740710-14691-1-git-send-email-jean.pihet@linaro.org> References: <1404740710-14691-1-git-send-email-jean.pihet@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org An event may occur when an mm is already released. As per commit 20afc60f892d285fde179ead4b24e6a7938c2f1b 'x86, perf: Check that current->mm is alive before getting user callchain' Signed-off-by: Jean Pihet Cc: Will Deacon Acked-by: Will Deacon --- arch/arm/kernel/perf_event.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 4238bcb..6493c4c 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -590,6 +590,10 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) } perf_callchain_store(entry, regs->ARM_pc); + + if (!current->mm) + return; + tail = (struct frame_tail __user *)regs->ARM_fp - 1; while ((entry->nr < PERF_MAX_STACK_DEPTH) && -- 1.8.1.2 -- 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/