From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964826Ab2DKX5r (ORCPT ); Wed, 11 Apr 2012 19:57:47 -0400 Received: from mail-pz0-f52.google.com ([209.85.210.52]:40940 "EHLO mail-pz0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964788Ab2DKXRD (ORCPT ); Wed, 11 Apr 2012 19:17:03 -0400 Message-Id: <20120411231026.059050794@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Wed, 11 Apr 2012 16:11:04 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jason Wessel Subject: [ 46/78] kgdb,debug_core: pass the breakpoint struct instead of address and memory In-Reply-To: <20120411231102.GA6404@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wessel commit 98b54aa1a2241b59372468bd1e9c2d207bdba54b upstream. There is extra state information that needs to be exposed in the kgdb_bpt structure for tracking how a breakpoint was installed. The debug_core only uses the the probe_kernel_write() to install breakpoints, but this is not enough for all the archs. Some arch such as x86 need to use text_poke() in order to install a breakpoint into a read only page. Passing the kgdb_bpt structure to kgdb_arch_set_breakpoint() and kgdb_arch_remove_breakpoint() allows other archs to set the type variable which indicates how the breakpoint was installed. Signed-off-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman --- include/linux/kgdb.h | 4 +-- kernel/debug/debug_core.c | 53 ++++++++++++++++++++-------------------------- 2 files changed, 26 insertions(+), 31 deletions(-) --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -207,8 +207,8 @@ extern void kgdb_arch_set_pc(struct pt_r /* Optional functions. */ extern int kgdb_validate_break_address(unsigned long addr); -extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr); -extern int kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle); +extern int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt); +extern int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt); /** * kgdb_arch_late - Perform any architecture specific initalization. --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -157,37 +157,39 @@ early_param("nokgdbroundup", opt_nokgdbr * Weak aliases for breakpoint management, * can be overriden by architectures when needed: */ -int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr) +int __weak kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt) { int err; - err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE); + err = probe_kernel_read(bpt->saved_instr, (char *)bpt->bpt_addr, + BREAK_INSTR_SIZE); if (err) return err; - - return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr, - BREAK_INSTR_SIZE); + err = probe_kernel_write((char *)bpt->bpt_addr, + arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE); + return err; } -int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle) +int __weak kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt) { - return probe_kernel_write((char *)addr, - (char *)bundle, BREAK_INSTR_SIZE); + return probe_kernel_write((char *)bpt->bpt_addr, + (char *)bpt->saved_instr, BREAK_INSTR_SIZE); } int __weak kgdb_validate_break_address(unsigned long addr) { - char tmp_variable[BREAK_INSTR_SIZE]; + struct kgdb_bkpt tmp; int err; - /* Validate setting the breakpoint and then removing it. In the + /* Validate setting the breakpoint and then removing it. If the * remove fails, the kernel needs to emit a bad message because we * are deep trouble not being able to put things back the way we * found them. */ - err = kgdb_arch_set_breakpoint(addr, tmp_variable); + tmp.bpt_addr = addr; + err = kgdb_arch_set_breakpoint(&tmp); if (err) return err; - err = kgdb_arch_remove_breakpoint(addr, tmp_variable); + err = kgdb_arch_remove_breakpoint(&tmp); if (err) printk(KERN_ERR "KGDB: Critical breakpoint error, kernel " "memory destroyed at: %lx", addr); @@ -231,7 +233,6 @@ static void kgdb_flush_swbreak_addr(unsi */ int dbg_activate_sw_breakpoints(void) { - unsigned long addr; int error; int ret = 0; int i; @@ -240,16 +241,15 @@ int dbg_activate_sw_breakpoints(void) if (kgdb_break[i].state != BP_SET) continue; - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_set_breakpoint(addr, - kgdb_break[i].saved_instr); + error = kgdb_arch_set_breakpoint(&kgdb_break[i]); if (error) { ret = error; - printk(KERN_INFO "KGDB: BP install failed: %lx", addr); + printk(KERN_INFO "KGDB: BP install failed: %lx", + kgdb_break[i].bpt_addr); continue; } - kgdb_flush_swbreak_addr(addr); + kgdb_flush_swbreak_addr(kgdb_break[i].bpt_addr); kgdb_break[i].state = BP_ACTIVE; } return ret; @@ -298,7 +298,6 @@ int dbg_set_sw_break(unsigned long addr) int dbg_deactivate_sw_breakpoints(void) { - unsigned long addr; int error; int ret = 0; int i; @@ -306,15 +305,14 @@ int dbg_deactivate_sw_breakpoints(void) for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { if (kgdb_break[i].state != BP_ACTIVE) continue; - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_remove_breakpoint(addr, - kgdb_break[i].saved_instr); + error = kgdb_arch_remove_breakpoint(&kgdb_break[i]); if (error) { - printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr); + printk(KERN_INFO "KGDB: BP remove failed: %lx\n", + kgdb_break[i].bpt_addr); ret = error; } - kgdb_flush_swbreak_addr(addr); + kgdb_flush_swbreak_addr(kgdb_break[i].bpt_addr); kgdb_break[i].state = BP_SET; } return ret; @@ -348,7 +346,6 @@ int kgdb_isremovedbreak(unsigned long ad int dbg_remove_all_break(void) { - unsigned long addr; int error; int i; @@ -356,12 +353,10 @@ int dbg_remove_all_break(void) for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { if (kgdb_break[i].state != BP_ACTIVE) goto setundefined; - addr = kgdb_break[i].bpt_addr; - error = kgdb_arch_remove_breakpoint(addr, - kgdb_break[i].saved_instr); + error = kgdb_arch_remove_breakpoint(&kgdb_break[i]); if (error) printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n", - addr); + kgdb_break[i].bpt_addr); setundefined: kgdb_break[i].state = BP_UNDEFINED; }