linux/arch/riscv/kernel/probes/decode-insn.c
Palmer Dabbelt 5dd6713331
RISC-V: probes: Treat the instruction stream as host-endian
Neither of these are actually correct: the instruction stream is defined
(for versions of the ISA manual newer than 2.2) as a stream of 16-bit
little-endian parcels, which is different than just being little-endian.
In theory we should represent this as a type, but we don't have any
concrete plans for the big endian stuff so it doesn't seem worth the
time -- we've got variants of this all over the place.

Instead I'm just dropping the unnecessary type conversion, which is a
NOP on LE systems but causes an sparse error as the types are all mixed
up.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-18 23:18:02 -08:00

49 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <asm/sections.h>
#include "decode-insn.h"
#include "simulate-insn.h"
/* Return:
* INSN_REJECTED If instruction is one not allowed to kprobe,
* INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
*/
enum probe_insn __kprobes
riscv_probe_decode_insn(probe_opcode_t *addr, struct arch_probe_insn *api)
{
probe_opcode_t insn = *addr;
/*
* Reject instructions list:
*/
RISCV_INSN_REJECTED(system, insn);
RISCV_INSN_REJECTED(fence, insn);
/*
* Simulate instructions list:
* TODO: the REJECTED ones below need to be implemented
*/
#ifdef CONFIG_RISCV_ISA_C
RISCV_INSN_REJECTED(c_j, insn);
RISCV_INSN_REJECTED(c_jr, insn);
RISCV_INSN_REJECTED(c_jal, insn);
RISCV_INSN_REJECTED(c_jalr, insn);
RISCV_INSN_REJECTED(c_beqz, insn);
RISCV_INSN_REJECTED(c_bnez, insn);
RISCV_INSN_REJECTED(c_ebreak, insn);
#endif
RISCV_INSN_REJECTED(auipc, insn);
RISCV_INSN_REJECTED(branch, insn);
RISCV_INSN_SET_SIMULATE(jal, insn);
RISCV_INSN_SET_SIMULATE(jalr, insn);
return INSN_GOOD;
}