Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757543AbYLPOtA (ORCPT ); Tue, 16 Dec 2008 09:49:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753763AbYLPOsv (ORCPT ); Tue, 16 Dec 2008 09:48:51 -0500 Received: from mga02.intel.com ([134.134.136.20]:7838 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753712AbYLPOsu (ORCPT ); Tue, 16 Dec 2008 09:48:50 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.36,231,1228118400"; d="scan'208";a="371330237" Date: Tue, 16 Dec 2008 15:48:42 +0100 From: Markus Metzger To: linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de, hpa@zytor.com Cc: markus.t.metzger@intel.com, markus.t.metzger@gmail.com, roland@redhat.com, eranian@googlemail.com Subject: [patch 1/3] x86, bts: clear bts bits on fork Message-ID: <20081216154842.A29980@sedona.ch.intel.com> Mime-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.2.5i Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3781 Lines: 126 Clear the DS context as well as the bts tracer and corresponding fields in task_struct on fork. Correct the CONFIG guard. Signed-off-by: Markus Metzger Reported-by: Ingo Molnar --- Index: ftrace/arch/x86/kernel/process_32.c =================================================================== --- ftrace.orig/arch/x86/kernel/process_32.c 2008-12-12 14:02:24.000000000 +0100 +++ ftrace/arch/x86/kernel/process_32.c 2008-12-12 14:33:19.000000000 +0100 @@ -251,7 +251,7 @@ tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET; put_cpu(); } -#ifdef CONFIG_X86_DS +#ifdef CONFIG_X86_PTRACE_BTS /* Free any BTS tracers that have not been properly released. */ if (unlikely(current->bts)) { ds_release_bts(current->bts); @@ -261,7 +261,7 @@ current->bts_buffer = NULL; current->bts_size = 0; } -#endif /* CONFIG_X86_DS */ +#endif /* CONFIG_X86_PTRACE_BTS */ } void flush_thread(void) @@ -343,6 +343,17 @@ kfree(p->thread.io_bitmap_ptr); p->thread.io_bitmap_max = 0; } + +#ifdef CONFIG_X86_DS + clear_tsk_thread_flag(p, TIF_DS_AREA_MSR); + p->thread.ds_ctx = NULL; +#endif +#ifdef CONFIG_X86_PTRACE_BTS + p->thread.bts_ovfl_signal = 0; +#endif + clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR); + p->thread.debugctlmsr = 0; + return err; } Index: ftrace/arch/x86/kernel/process_64.c =================================================================== --- ftrace.orig/arch/x86/kernel/process_64.c 2008-12-12 14:02:24.000000000 +0100 +++ ftrace/arch/x86/kernel/process_64.c 2008-12-12 14:32:38.000000000 +0100 @@ -248,7 +248,7 @@ t->io_bitmap_max = 0; put_cpu(); } -#ifdef CONFIG_X86_DS +#ifdef CONFIG_X86_PTRACE_BTS /* Free any BTS tracers that have not been properly released. */ if (unlikely(current->bts)) { ds_release_bts(current->bts); @@ -258,7 +258,7 @@ current->bts_buffer = NULL; current->bts_size = 0; } -#endif /* CONFIG_X86_DS */ +#endif /* CONFIG_X86_PTRACE_BTS */ } void flush_thread(void) @@ -388,6 +388,17 @@ if (err) goto out; } + +#ifdef CONFIG_X86_DS + clear_tsk_thread_flag(p, TIF_DS_AREA_MSR); + p->thread.ds_ctx = NULL; +#endif +#ifdef CONFIG_X86_PTRACE_BTS + p->thread.bts_ovfl_signal = 0; +#endif + clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR); + p->thread.debugctlmsr = 0; + err = 0; out: if (err && p->thread.io_bitmap_ptr) { Index: ftrace/kernel/fork.c =================================================================== --- ftrace.orig/kernel/fork.c 2008-12-12 14:02:24.000000000 +0100 +++ ftrace/kernel/fork.c 2008-12-12 14:29:43.000000000 +0100 @@ -1102,7 +1102,11 @@ #ifdef CONFIG_DEBUG_MUTEXES p->blocked_on = NULL; /* not blocked yet */ #endif - +#ifdef CONFIG_X86_PTRACE_BTS + p->bts = NULL; + p->bts_buffer = NULL; + p->bts_size = 0; +#endif /* Perform scheduler related setup. Assign this task to a CPU. */ sched_fork(p, clone_flags); --------------------------------------------------------------------- Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen Germany Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Douglas Lusk, Peter Gleissner, Hannes Schwaderer Registergericht: Muenchen HRB 47456 Ust.-IdNr. VAT Registration No.: DE129385895 Citibank Frankfurt (BLZ 502 109 00) 600119052 This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. -- 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/