From 65b8c7226eb74a7db1a618d69d5cb0cb5f13e99d Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 26 Apr 2012 08:31:19 +0000 Subject: [PATCH] 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/ftrace.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index d56848afd2cf..6f33296a0570 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -63,11 +63,9 @@ ftrace_modify_code(unsigned long ip, unsigned int old, unsigned int new) 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 @@ __ftrace_make_nop(struct module *mod, */ 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 @@ __ftrace_make_nop(struct module *mod, 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 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 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 */ -- 2.30.2