riscv: kprobes: Prevent probes in breakpoint handlers

The ftrace selftest multiple_kprobes.tc registers kprobe events on
the first 256 text symbols from /proc/kallsyms. If handle_break() is
selected as a probe target on RISC-V, the breakpoint exception path
can trap again before it reaches the kprobe breakpoint handler. That
recursively enters do_trap_break() and can make the system
unresponsive.

Mark handle_break() and its local probe dispatch helpers as nokprobe
symbols so they are added to the kprobe blacklist, matching other
low-level breakpoint exception paths.

Signed-off-by: Rui Qi <qirui.001@bytedance.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20260806043807.2583001-1-qirui.001@bytedance.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
This commit is contained in:
Rui Qi 2026-08-07 19:24:33 -06:00 • committed by Paul Walmsley
commit e7d8ea6c6d