uprobes/x86: Shift "insn_complete" from branch_setup_xol_ops() to uprobe_init_insn()

Change uprobe_init_insn() to make insn_complete() == T, this makes
other insn_get_*() calls unnecessary.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

1 files changed, 4 insertions, 9 deletions

diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index b3b25ddc04fb..98d7db50f425 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -209,8 +209,11 @@ static int uprobe_init_insn(struct arch_uprobe *auprobe, struct insn *insn, bool
         u32 volatile *good_insns;
 
         insn_init(insn, auprobe->insn, x86_64);
+        /* has the side-effect of processing the entire instruction */
+        insn_get_length(insn);
+        if (WARN_ON_ONCE(!insn_complete(insn)))
+                return -ENOEXEC;
 
-        insn_get_opcode(insn);
         if (is_prefix_bad(insn))
                 return -ENOTSUPP;
 
@@ -283,8 +286,6 @@ handle_riprel_insn(struct arch_uprobe *auprobe, struct insn *insn)
          * is the immediate operand.
          */
         cursor = auprobe->insn + insn_offset_modrm(insn);
-        insn_get_length(insn);
-
         /*
          * Convert from rip-relative addressing to indirect addressing
          * via a scratch register.  Change the r/m field from 0x5 (%rip)
@@ -564,11 +565,6 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn)
         u8 opc1 = OPCODE1(insn);
         int i;
 
-        /* has the side-effect of processing the entire instruction */
-        insn_get_length(insn);
-        if (WARN_ON_ONCE(!insn_complete(insn)))
-                return -ENOEXEC;
-
         switch (opc1) {
         case 0xeb:      /* jmp 8 */
         case 0xe9:      /* jmp 32 */
@@ -654,7 +650,6 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm,
                 fix_ip = false;
                 break;
         case 0xff:
-                insn_get_modrm(&insn);
                 switch (MODRM_REG(&insn)) {
                 case 2: case 3:                 /* call or lcall, indirect */
                         fix_call = true;