From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/samples/hw_breakpoint/Makefile | 1 + kernel/samples/hw_breakpoint/data_breakpoint.c | 90 ++++++++++++++++++++++++++ 2 files changed, 91 insertions(+) create mode 100644 kernel/samples/hw_breakpoint/Makefile create mode 100644 kernel/samples/hw_breakpoint/data_breakpoint.c (limited to 'kernel/samples/hw_breakpoint') diff --git a/kernel/samples/hw_breakpoint/Makefile b/kernel/samples/hw_breakpoint/Makefile new file mode 100644 index 000000000..0f5c31c2f --- /dev/null +++ b/kernel/samples/hw_breakpoint/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_SAMPLE_HW_BREAKPOINT) += data_breakpoint.o diff --git a/kernel/samples/hw_breakpoint/data_breakpoint.c b/kernel/samples/hw_breakpoint/data_breakpoint.c new file mode 100644 index 000000000..ef7f32291 --- /dev/null +++ b/kernel/samples/hw_breakpoint/data_breakpoint.c @@ -0,0 +1,90 @@ +/* + * data_breakpoint.c - Sample HW Breakpoint file to watch kernel data address + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * usage: insmod data_breakpoint.ko ksym= + * + * This file is a kernel module that places a breakpoint over ksym_name kernel + * variable using Hardware Breakpoint register. The corresponding handler which + * prints a backtrace is invoked every time a write operation is performed on + * that variable. + * + * Copyright (C) IBM Corporation, 2009 + * + * Author: K.Prasad + */ +#include /* Needed by all modules */ +#include /* Needed for KERN_INFO */ +#include /* Needed for the macros */ +#include + +#include +#include + +struct perf_event * __percpu *sample_hbp; + +static char ksym_name[KSYM_NAME_LEN] = "pid_max"; +module_param_string(ksym, ksym_name, KSYM_NAME_LEN, S_IRUGO); +MODULE_PARM_DESC(ksym, "Kernel symbol to monitor; this module will report any" + " write operations on the kernel symbol"); + +static void sample_hbp_handler(struct perf_event *bp, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + printk(KERN_INFO "%s value is changed\n", ksym_name); + dump_stack(); + printk(KERN_INFO "Dump stack from sample_hbp_handler\n"); +} + +static int __init hw_break_module_init(void) +{ + int ret; + struct perf_event_attr attr; + + hw_breakpoint_init(&attr); + attr.bp_addr = kallsyms_lookup_name(ksym_name); + attr.bp_len = HW_BREAKPOINT_LEN_4; + attr.bp_type = HW_BREAKPOINT_W | HW_BREAKPOINT_R; + + sample_hbp = register_wide_hw_breakpoint(&attr, sample_hbp_handler, NULL); + if (IS_ERR((void __force *)sample_hbp)) { + ret = PTR_ERR((void __force *)sample_hbp); + goto fail; + } + + printk(KERN_INFO "HW Breakpoint for %s write installed\n", ksym_name); + + return 0; + +fail: + printk(KERN_INFO "Breakpoint registration failed\n"); + + return ret; +} + +static void __exit hw_break_module_exit(void) +{ + unregister_wide_hw_breakpoint(sample_hbp); + printk(KERN_INFO "HW Breakpoint for %s write uninstalled\n", ksym_name); +} + +module_init(hw_break_module_init); +module_exit(hw_break_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("K.Prasad"); +MODULE_DESCRIPTION("ksym breakpoint"); -- cgit 1.2.3-korg