From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757856AbbDVS21 (ORCPT ); Wed, 22 Apr 2015 14:28:27 -0400 Received: from mga03.intel.com ([134.134.136.65]:52313 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757677AbbDVS1o (ORCPT ); Wed, 22 Apr 2015 14:27:44 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,625,1422950400"; d="scan'208";a="713753729" Subject: [PATCH 04/17] x86, mpx: trace entry to bounds exception paths To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, tglx@linutronix.de, Dave Hansen , dave.hansen@linux.intel.com From: Dave Hansen Date: Wed, 22 Apr 2015 11:27:34 -0700 References: <20150422182729.0512E57D@viggo.jf.intel.com> In-Reply-To: <20150422182729.0512E57D@viggo.jf.intel.com> Message-Id: <20150422182734.5C90CD6B@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen There are two basic things that can happen as the result of a bounds exception (#BR): 1. We allocate a new bounds table 2. We pass up a bounds exception to userspace. This patch adds a trace point for the case where we are passing the exception up to userspace with a signal. We are also explicit that we're printing out the inverse of the 'upper' that we encounter. If you want to filter, for instance, you need to ~ the value first. Signed-off-by: Dave Hansen --- b/arch/x86/include/asm/trace/mpx.h | 25 +++++++++++++++++++++++++ b/arch/x86/mm/mpx.c | 2 ++ 2 files changed, 27 insertions(+) diff -puN arch/x86/include/asm/trace/mpx.h~x86-mpx-trace-1 arch/x86/include/asm/trace/mpx.h --- a/arch/x86/include/asm/trace/mpx.h~x86-mpx-trace-1 2015-04-22 11:16:19.051857884 -0700 +++ b/arch/x86/include/asm/trace/mpx.h 2015-04-22 11:16:19.056858109 -0700 @@ -8,6 +8,31 @@ #ifdef CONFIG_X86_INTEL_MPX +TRACE_EVENT(mpx_bounds_register_exception, + + TP_PROTO(void *addr_referenced, + struct bndreg *bndreg), + TP_ARGS(addr_referenced, bndreg), + + TP_STRUCT__entry( + __field(void *, addr_referenced) + __field(u64, lower_bound) + __field(u64, upper_bound) + ), + + TP_fast_assign( + __entry->addr_referenced = addr_referenced; + __entry->lower_bound = bndreg->lower_bound; + __entry->upper_bound = bndreg->upper_bound; + ), + + TP_printk("address referenced: 0x%p bounds: lower: 0x%llx ~upper: 0x%llx", + __entry->addr_referenced, + __entry->lower_bound, + ~__entry->upper_bound + ) +); + TRACE_EVENT(bounds_exception_mpx, TP_PROTO(struct bndcsr *bndcsr), diff -puN arch/x86/mm/mpx.c~x86-mpx-trace-1 arch/x86/mm/mpx.c --- a/arch/x86/mm/mpx.c~x86-mpx-trace-1 2015-04-22 11:16:19.053857974 -0700 +++ b/arch/x86/mm/mpx.c 2015-04-22 11:16:19.057858154 -0700 @@ -16,6 +16,7 @@ #include #include #include +#include #include #define CREATE_TRACE_POINTS @@ -337,6 +338,7 @@ siginfo_t *mpx_generate_siginfo(struct p err = -EINVAL; goto err_out; } + trace_mpx_bounds_register_exception(info->si_addr, bndreg); return info; err_out: /* info might be NULL, but kfree() handles that */ _