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Subject[PATCH] RISC-V: probes: Treat the instruction stream as host-endian
Date
From
From: Palmer Dabbelt <palmerdabbelt@google.com>

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>
---
arch/riscv/kernel/probes/decode-insn.c | 2 +-
arch/riscv/kernel/probes/kprobes.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kernel/probes/decode-insn.c b/arch/riscv/kernel/probes/decode-insn.c
index 0876c304ca77..0ed043acc882 100644
--- a/arch/riscv/kernel/probes/decode-insn.c
+++ b/arch/riscv/kernel/probes/decode-insn.c
@@ -16,7 +16,7 @@
enum probe_insn __kprobes
riscv_probe_decode_insn(probe_opcode_t *addr, struct arch_probe_insn *api)
{
- probe_opcode_t insn = le32_to_cpu(*addr);
+ probe_opcode_t insn = *addr;

/*
* Reject instructions list:
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
index e60893bd87db..a2ec18662fee 100644
--- a/arch/riscv/kernel/probes/kprobes.c
+++ b/arch/riscv/kernel/probes/kprobes.c
@@ -57,7 +57,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
}

/* copy instruction */
- p->opcode = le32_to_cpu(*p->addr);
+ p->opcode = *p->addr;

/* decode instruction */
switch (riscv_probe_decode_insn(p->addr, &p->ainsn.api)) {
--
2.30.0.280.ga3ce27912f-goog
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