linux/arch/riscv/include/asm/probes.h

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riscv: Add kprobes supported This patch enables "kprobe & kretprobe" to work with ftrace interface. It utilized software breakpoint as single-step mechanism. Some instructions which can't be single-step executed must be simulated in kernel execution slot, such as: branch, jal, auipc, la ... Some instructions should be rejected for probing and we use a blacklist to filter, such as: ecall, ebreak, ... We use ebreak & c.ebreak to replace origin instruction and the kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed. In execution slot we add ebreak behind original instruction to simulate a single-setp mechanism. The patch is based on packi's work [1] and csky's work [2]. - The kprobes_trampoline.S is all from packi's patch - The single-step mechanism is new designed for riscv without hw single-step trap - The simulation codes are from csky - Frankly, all codes refer to other archs' implementation [1] https://lore.kernel.org/linux-riscv/20181113195804.22825-1-me@packi.ch/ [2] https://lore.kernel.org/linux-csky/20200403044150.20562-9-guoren@kernel.org/ Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Patrick Stählin <me@packi.ch> Signed-off-by: Patrick Stählin <me@packi.ch> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Zong Li <zong.li@sifive.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: Patrick Stählin <me@packi.ch> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-17 16:01:42 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_RISCV_PROBES_H
#define _ASM_RISCV_PROBES_H
typedef u32 probe_opcode_t;
typedef bool (probes_handler_t) (u32 opcode, unsigned long addr, struct pt_regs *);
/* architecture specific copy of original instruction */
struct arch_probe_insn {
probe_opcode_t *insn;
probes_handler_t *handler;
/* restore address after simulation */
unsigned long restore;
};
#ifdef CONFIG_KPROBES
typedef u32 kprobe_opcode_t;
struct arch_specific_insn {
struct arch_probe_insn api;
};
#endif
#endif /* _ASM_RISCV_PROBES_H */