From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759886AbYDVAWE (ORCPT ); Mon, 21 Apr 2008 20:22:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755265AbYDVAVy (ORCPT ); Mon, 21 Apr 2008 20:21:54 -0400 Received: from smtp1.dnsmadeeasy.com ([205.234.170.144]:55969 "EHLO smtp1.dnsmadeeasy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757300AbYDVAVx (ORCPT ); Mon, 21 Apr 2008 20:21:53 -0400 X-Authenticated-Name: js.dnsmadeeasy X-Transit-System: In case of SPAM please contact abuse@dnsmadeeasy.com Message-ID: <480D2F9E.4060408@avtrex.com> Date: Mon, 21 Apr 2008 17:21:50 -0700 From: David Daney User-Agent: Thunderbird 2.0.0.12 (X11/20080226) MIME-Version: 1.0 To: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Subject: [Patch 4/6] Watch trap handling for HARDWARE_WATCHPOINTS. References: <480D2151.2020701@avtrex.com> In-Reply-To: <480D2151.2020701@avtrex.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 22 Apr 2008 00:21:51.0846 (UTC) FILETIME=[DCA69060:01C8A40E] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In this portion of the patch we hook up the watch trap handler. When the trap occurs, we copy the register contents into the thread_struct and send SIGTRAP. If the current thread was not expecting the trap, the watch register values must have been left over from a different context and we just clear the registers and return. Also I turn off the message the prints on each trap, as these traps are now expected. Signed-off-by: David Daney --- arch/mips/kernel/genex.S | 4 ++++ arch/mips/kernel/traps.c | 13 +++++++++++++ 2 files changed, 17 insertions(+), 0 deletions(-) diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index c6ada98..15a9bde 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -416,7 +416,11 @@ NESTED(nmi_handler, PT_SIZE, sp) BUILD_HANDLER tr tr sti silent /* #13 */ BUILD_HANDLER fpe fpe fpe silent /* #15 */ BUILD_HANDLER mdmx mdmx sti silent /* #22 */ +#ifdef CONFIG_HARDWARE_WATCHPOINTS + BUILD_HANDLER watch watch sti silent /* #23 */ +#else BUILD_HANDLER watch watch sti verbose /* #23 */ +#endif BUILD_HANDLER mcheck mcheck cli verbose /* #24 */ BUILD_HANDLER mt mt sti silent /* #25 */ BUILD_HANDLER dsp dsp sti silent /* #26 */ diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 984c0d0..6a5f3f0 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -887,6 +887,18 @@ asmlinkage void do_mdmx(struct pt_regs *regs) asmlinkage void do_watch(struct pt_regs *regs) { +#ifdef CONFIG_HARDWARE_WATCHPOINTS + /* + * If the current thread has the watch registers loaded, save + * their values and send SIGTRAP. Otherwise another thread + * left the registers set, clear them and continue. + */ + if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) { + mips_read_watch_registers(); + force_sig(SIGTRAP, current); + } else + mips_clear_watch_registers(); +#else if (board_watchpoint_handler) { (*board_watchpoint_handler)(regs); return; @@ -899,6 +911,7 @@ asmlinkage void do_watch(struct pt_regs *regs) dump_tlb_all(); show_regs(regs); panic("Caught WATCH exception - probably caused by stack overflow."); +#endif } asmlinkage void do_mcheck(struct pt_regs *regs) -- 1.5.5