rseq/selftests: powerpc code signature: generate valid instructions

Use "twui" as the guard instruction for the restartable sequence abort handler. Signed-off-by: Mathieu Desnoyers <[email protected]> CC: Benjamin Herrenschmidt <[email protected]> CC: Paul Mackerras <[email protected]> CC: Michael Ellerman <[email protected]> CC: Boqun Feng <[email protected]> CC: Peter Zijlstra <[email protected]> CC: "Paul E. McKenney" <[email protected]> CC: Alan Modra <[email protected]> CC: [email protected] Signed-off-by: Shuah Khan <[email protected]>
laijs · May 7, 2019 · 496fd0f · 496fd0f
1 parent 7cd4ce2
commit 496fd0f
Showing 1 changed file with 9 additions and 1 deletion.
diff --git a/tools/testing/selftests/rseq/rseq-ppc.h b/tools/testing/selftests/rseq/rseq-ppc.h
@@ -6,7 +6,15 @@
  * (C) Copyright 2016-2018 - Boqun Feng <[email protected]>
  */
 
-#define RSEQ_SIG	0x53053053
+/*
+ * RSEQ_SIG is used with the following trap instruction:
+ *
+ * powerpc-be:    0f e5 00 0b           twui   r5,11
+ * powerpc64-le:  0b 00 e5 0f           twui   r5,11
+ * powerpc64-be:  0f e5 00 0b           twui   r5,11
+ */
+
+#define RSEQ_SIG	0x0fe5000b
 
 #define rseq_smp_mb()		__asm__ __volatile__ ("sync"	::: "memory", "cc")
 #define rseq_smp_lwsync()	__asm__ __volatile__ ("lwsync"	::: "memory", "cc")