/* * 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"); c7289526eed96541a0654'>ipv4/xfrm4_output.c
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authorJohan Hovold <johan@kernel.org>2017-01-30 11:26:38 +0100
committerJiri Kosina <jkosina@suse.cz>2017-01-31 12:59:32 +0100
commit7a7b5df84b6b4e5d599c7289526eed96541a0654 (patch)
treecf7514c7ddf4410fe37ca9099a2785e1cf08fa7d /net/ipv4/xfrm4_output.c
parent877a021e08ccb6434718c0cc781fdf943c884cc0 (diff)
HID: cp2112: fix sleep-while-atomic
A recent commit fixing DMA-buffers on stack added a shared transfer buffer protected by a spinlock. This is broken as the USB HID request callbacks can sleep. Fix this up by replacing the spinlock with a mutex. Fixes: 1ffb3c40ffb5 ("HID: cp2112: make transfer buffers DMA capable") Cc: stable <stable@vger.kernel.org> # 4.9 Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'net/ipv4/xfrm4_output.c')