powerpc/ftrace: Use patch_instruction instead of probe_kernel_write()
The patch_instruction() interface is made to modify kernel text. It is
safer to use that then the probe_kernel_write() when modifying kernel
code.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index d56848a..6f33296 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -63,11 +63,9 @@
return -EINVAL;
/* replace the text with the new text */
- if (probe_kernel_write((void *)ip, &new, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, new))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
@@ -212,12 +210,9 @@
*/
op = 0x48000008; /* b +8 */
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
-
- flush_icache_range(ip, ip + 8);
-
return 0;
}
@@ -286,11 +281,9 @@
op = PPC_INST_NOP;
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
#endif /* PPC64 */
@@ -426,11 +419,9 @@
pr_devel("write to %lx\n", rec->ip);
- if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
+ if (patch_instruction((unsigned int *)ip, op))
return -EPERM;
- flush_icache_range(ip, ip + 8);
-
return 0;
}
#endif /* CONFIG_PPC64 */