Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756740AbYH1WIK (ORCPT ); Thu, 28 Aug 2008 18:08:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757965AbYH1WHk (ORCPT ); Thu, 28 Aug 2008 18:07:40 -0400 Received: from smtp1.dnsmadeeasy.com ([205.234.170.134]:59173 "EHLO smtp1.dnsmadeeasy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757941AbYH1WHj (ORCPT ); Thu, 28 Aug 2008 18:07:39 -0400 X-Authenticated-Name: js.dnsmadeeasy X-Transit-System: In case of SPAM please contact abuse@dnsmadeeasy.com Message-ID: <48B721A9.4070201@avtrex.com> Date: Thu, 28 Aug 2008 15:07:37 -0700 From: David Daney User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Subject: [Patch 4/6] MIPS: Watch exception handling for HARDWARE_WATCHPOINTS. References: <48B71ADD.601@avtrex.com> In-Reply-To: <48B71ADD.601@avtrex.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 28 Aug 2008 22:07:37.0729 (UTC) FILETIME=[7B4F9710:01C9095A] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2287 Lines: 67 Here we hook up the watch exception handler so that it sends SIGTRAP when the hardware watch registers are triggered. Signed-off-by: David Daney --- arch/mips/kernel/genex.S | 4 ++++ arch/mips/kernel/traps.c | 14 +++++++++----- 2 files changed, 13 insertions(+), 5 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 6bee290..5fbf591 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -908,12 +909,15 @@ asmlinkage void do_mdmx(struct pt_regs *regs) asmlinkage void do_watch(struct pt_regs *regs) { /* - * We use the watch exception where available to detect stack - * overflows. + * 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. */ - dump_tlb_all(); - show_regs(regs); - panic("Caught WATCH exception - probably caused by stack overflow."); + if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) { + mips_read_watch_registers(); + force_sig(SIGTRAP, current); + } else + mips_clear_watch_registers(); } asmlinkage void do_mcheck(struct pt_regs *regs) -- 1.5.5.1 -- 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/