Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932182Ab0BBTBZ (ORCPT ); Tue, 2 Feb 2010 14:01:25 -0500 Received: from verein.lst.de ([213.95.11.210]:38063 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932149Ab0BBTBV (ORCPT ); Tue, 2 Feb 2010 14:01:21 -0500 Date: Tue, 2 Feb 2010 20:00:54 +0100 From: Christoph Hellwig To: roland@redhat.com, oleg@redhat.com, akpm@linux-foundation.org, takata@linux-m32r.org Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: [PATCH, RFC 14/14] m32r: use generic ptrace_resume code Message-ID: <20100202190054.GN3630@lst.de> References: <20100202185755.GA3630@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100202185755.GA3630@lst.de> User-Agent: Mutt/1.3.28i X-Spam-Score: 0 () Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4295 Lines: 151 Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT, PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining arch_has_single_step in and implementing the user_enable_single_step and user_disable_single_step functions, which also causes the breakpoint information to be cleared on fork, which could be considered a bug fix. Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which it previously wasn't, which is consistent with all architectures using the modern ptrace code. The old code only disables the breakpoints on PTRACE_KILL, while after this patch this also happens for PTRACE_CONT and PTRACE_SYSCALL which matches the behaviour of the other architetures. I think this is a bugfixes, but please double verify this is correct. Signed-off-by: Christoph Hellwig Index: linux-2.6/arch/m32r/include/asm/ptrace.h =================================================================== --- linux-2.6.orig/arch/m32r/include/asm/ptrace.h 2010-02-02 19:26:37.456003660 +0100 +++ linux-2.6/arch/m32r/include/asm/ptrace.h 2010-02-02 19:26:49.405264333 +0100 @@ -120,6 +120,8 @@ struct pt_regs { #include /* M32R_PSW_BSM, M32R_PSW_BPM */ +#define arch_has_single_step() (1) + struct task_struct; extern void init_debug_traps(struct task_struct *); #define arch_ptrace_attach(child) \ Index: linux-2.6/arch/m32r/kernel/ptrace.c =================================================================== --- linux-2.6.orig/arch/m32r/kernel/ptrace.c 2010-02-02 19:26:54.353253780 +0100 +++ linux-2.6/arch/m32r/kernel/ptrace.c 2010-02-02 19:29:39.935253922 +0100 @@ -580,6 +580,35 @@ init_debug_traps(struct task_struct *chi } } +void user_enable_single_step(struct task_struct *child) +{ + unsigned long next_pc; + unsigned long pc, insn; + + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + + /* Compute next pc. */ + pc = get_stack_long(child, PT_BPC); + + if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0) + != sizeof(insn)) + break; + + compute_next_pc(insn, pc, &next_pc, child); + if (next_pc & 0x80000000) + break; + + if (embed_debug_trap(child, next_pc)) + break; + + invalidate_cache(); +} + +void user_disable_single_step(struct task_struct *child) +{ + unregister_all_debug_traps(child); + invalidate_cache(); +} /* * Called by kernel/ptrace.c when detaching.. @@ -612,74 +641,6 @@ arch_ptrace(struct task_struct *child, l ret = ptrace_write_user(child, addr, data); break; - /* - * continue/restart and stop at next (return from) syscall - */ - case PTRACE_SYSCALL: - case PTRACE_CONT: - ret = -EIO; - if (!valid_signal(data)) - break; - if (request == PTRACE_SYSCALL) - set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - else - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - child->exit_code = data; - wake_up_process(child); - ret = 0; - break; - - /* - * make the child exit. Best I can do is send it a sigkill. - * perhaps it should be put in the status that it wants to - * exit. - */ - case PTRACE_KILL: { - ret = 0; - unregister_all_debug_traps(child); - invalidate_cache(); - if (child->exit_state == EXIT_ZOMBIE) /* already dead */ - break; - child->exit_code = SIGKILL; - wake_up_process(child); - break; - } - - /* - * execute single instruction. - */ - case PTRACE_SINGLESTEP: { - unsigned long next_pc; - unsigned long pc, insn; - - ret = -EIO; - if (!valid_signal(data)) - break; - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - - /* Compute next pc. */ - pc = get_stack_long(child, PT_BPC); - - if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0) - != sizeof(insn)) - break; - - compute_next_pc(insn, pc, &next_pc, child); - if (next_pc & 0x80000000) - break; - - if (embed_debug_trap(child, next_pc)) - break; - - invalidate_cache(); - child->exit_code = data; - - /* give it a chance to run. */ - wake_up_process(child); - ret = 0; - break; - } - case PTRACE_GETREGS: ret = ptrace_getregs(child, (void __user *)data); break; -- 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/