[PATCH v2 13/21] x86/sev-es: Convert to insn_decode()

From: Borislav Petkov
Date: Wed Feb 24 2021 - 06:10:36 EST


From: Borislav Petkov <bp@xxxxxxx>

Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/kernel/sev-es.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 6513e94d53f2..d2880a305772 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -244,7 +244,6 @@ static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt,
static enum es_result __vc_decode_user_insn(struct es_em_ctxt *ctxt)
{
char buffer[MAX_INSN_SIZE];
- enum es_result ret;
int res;

res = insn_fetch_from_user(ctxt->regs, buffer);
@@ -258,16 +257,16 @@ static enum es_result __vc_decode_user_insn(struct es_em_ctxt *ctxt)
if (!insn_decode_from_regs(&ctxt->insn, ctxt->regs, buffer, res))
return ES_DECODE_FAILED;

- ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED;
-
- return ret;
+ if (ctxt->insn.immediate.got)
+ return ES_OK;
+ else
+ return ES_DECODE_FAILED;
}

static enum es_result __vc_decode_kern_insn(struct es_em_ctxt *ctxt)
{
char buffer[MAX_INSN_SIZE];
- enum es_result ret;
- int res;
+ int res, ret;

res = vc_fetch_insn_kernel(ctxt, buffer);
if (res) {
@@ -277,12 +276,11 @@ static enum es_result __vc_decode_kern_insn(struct es_em_ctxt *ctxt)
return ES_EXCEPTION;
}

- insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1);
- insn_get_length(&ctxt->insn);
-
- ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED;
-
- return ret;
+ ret = insn_decode(&ctxt->insn, buffer, MAX_INSN_SIZE, INSN_MODE_64);
+ if (ret < 0)
+ return ES_DECODE_FAILED;
+ else
+ return ES_OK;
}

static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt)
--
2.29.2