Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932457AbZJEKYe (ORCPT ); Mon, 5 Oct 2009 06:24:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932313AbZJEKYe (ORCPT ); Mon, 5 Oct 2009 06:24:34 -0400 Received: from 124x34x33x190.ap124.ftth.ucom.ne.jp ([124.34.33.190]:33814 "EHLO master.linux-sh.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758687AbZJEKYd (ORCPT ); Mon, 5 Oct 2009 06:24:33 -0400 Date: Mon, 5 Oct 2009 19:23:06 +0900 From: Paul Mundt To: "K.Prasad" , Ingo Molnar Cc: Alan Stern , Frederic Weisbecker , linux-kernel@vger.kernel.org Subject: [PATCH -tip] x86: hw-breakpoints: Actually flush thread breakpoints in flush_thread(). Message-ID: <20091005102306.GA7889@linux-sh.org> Mail-Followup-To: Paul Mundt , "K.Prasad" , Ingo Molnar , Alan Stern , Frederic Weisbecker , linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1425 Lines: 40 [ I noticed this whilst hacking up SH support, applies to the current tracing/hw-breakpoints topic branch. ] flush_thread() tries to do a TIF_DEBUG check before calling in to flush_thread_hw_breakpoint() (which subsequently clears the thread flag), but for some reason, the x86 code is manually clearing TIF_DEBUG immediately before the test, so this path will never be taken. This kills off the erroneous clear_tsk_thread_flag() and lets flush_thread_hw_breakpoint() actually get invoked. Presumably folks were getting lucky with testing and the free_thread_info() -> free_thread_xstate() path was taking care of the flush there. Signed-off-by: Paul Mundt --- arch/x86/kernel/process.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 1092a1a..c62f647 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -110,8 +110,6 @@ void flush_thread(void) } #endif - clear_tsk_thread_flag(tsk, TIF_DEBUG); - if (unlikely(test_tsk_thread_flag(tsk, TIF_DEBUG))) flush_thread_hw_breakpoint(tsk); memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); -- 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/