From mboxrd@z Thu Jan 1 00:00:00 1970 From: wangnan0@huawei.com (Wang Nan) Date: Thu, 12 Feb 2015 20:21:20 +0800 Subject: [RFC PATCH v2 23/26] early kprobes: x86: arch_restore_optimized_kprobe(). In-Reply-To: <1423743476-11927-1-git-send-email-wangnan0@huawei.com> References: <1423743476-11927-1-git-send-email-wangnan0@huawei.com> Message-ID: <1423743680-13029-1-git-send-email-wangnan0@huawei.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org arch_restore_optimized_kprobe() can be used to temporarily restore probed instruction. It will actually disable optimized kprobe. Signed-off-by: Wang Nan --- arch/x86/kernel/kprobes/opt.c | 26 ++++++++++++++++++++++++++ include/linux/kprobes.h | 1 + 2 files changed, 27 insertions(+) diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index f3ea954..12332c2 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -486,4 +487,29 @@ void arch_fix_ftrace_early_kprobe(struct optimized_kprobe *op) memcpy(&list_p->opcode, correct_nop5, sizeof(kprobe_opcode_t)); } + +static int do_restore_kprobe(void *p) +{ + struct optimized_kprobe *op = p; + u8 insn_buf[RELATIVEJUMP_SIZE]; + + memcpy(insn_buf, &op->kp.opcode, sizeof(kprobe_opcode_t)); + memcpy(insn_buf + INT3_SIZE, + op->optinsn.copied_insn, + RELATIVE_ADDR_SIZE); + text_poke(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE); + return 0; +} + +void arch_restore_optimized_kprobe(struct optimized_kprobe *op) +{ + u32 mask = KPROBE_FLAG_EARLY | + KPROBE_FLAG_OPTIMIZED | + KPROBE_FLAG_FTRACE; + + if ((op->kp.flags & mask) != mask) + return; + + stop_machine(do_restore_kprobe, op, NULL); +} #endif diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 990d04b..92aafa7 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -461,6 +461,7 @@ extern int arch_prepare_kprobe_ftrace(struct kprobe *p); #ifdef CONFIG_EARLY_KPROBES extern void arch_fix_ftrace_early_kprobe(struct optimized_kprobe *p); +extern void arch_restore_optimized_kprobe(struct optimized_kprobe *p); #endif #endif -- 1.8.4