动态硬件断点内存损坏检测 · v1

新增 HAVE_REINSTALL_HW_BREAKPOINT Kconfig 符号，允许架构在原子上下文中原地更新硬件断点，无需释放和重新分配槽位。

重构 x86 硬件断点安装/卸载代码，减少重复并缩小代码体积，为引入 arch_reinstall_hw_breakpoint() 做准备。

为 x86 实现 arch_reinstall_hw_breakpoint()，支持在原子上下文中原地更新断点，并在 setup_hwbp() 中清除旧 len/type 位避免合并错误。

新增 modify_wide_hw_breakpoint_local() API，允许在支持 HAVE_REINSTALL_HW_BREAKPOINT 的架构上在线更新断点地址，但限制类型兼容性。

实现 KWatch 的表达式解析器 kwatch_deref_parse() 和运行时解引用引擎 kwatch_deref_resolve()，支持基于函数参数和偏移链的地址追踪。

为 KWatch 实现基于 cmpxchg 的无锁 per-task 上下文池，在 kprobe/NMI 上下文中无需分配或加锁即可管理窗口状态。

导出 stack_trace_save_regs() 函数，使模块能从 pt_regs 捕获栈回溯，供 KWatch 记录断点触发时的调用栈。

On Wed, 15 Jul 2026 02:32:06 +0800 Jinchao Wang wangjinchao600@gmail.com wrote: > — /dev/null > +++ b/include/trace/events/kwatch.h > @@ -0,0 +1,57 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +

Open and close the watch window with a kretprobe on the target function: the entry handler tracks per-task nesting depth and, when the configured depth is reached, resolves the watch expression and ar

Global variables have no function whose execution can bound the watch window. Provide one: a kernel thread sleeps for the configured duration inside a dedicated noinline function, kwatch_global_anchor

Wire the pieces together behind a single debugfs file, /sys/kernel/debug/kwatch/config. Writing a key=value configuration string stops any active session and starts a new one; reading shows the active

Cover base anchors (stack, argN, absolute address), positive and negative offsets, dereference chains, and rejection of malformed expressions (missing offsets, bad argument index, junk offsets). Sign

Describe what KWatch is for, how it compares with KASAN and KFENCE, the debugfs configuration interface, the watch expression syntax, how to read hits from the trace buffer (including after a crash),