diff options
| author | Ingo Molnar <[email protected]> | 2020-02-24 11:36:09 +0100 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2020-02-24 11:36:09 +0100 |
| commit | 546121b65f47384e11ec1fa2e55449fc9f4846b2 (patch) | |
| tree | 8f18470ec7c0c77b0f48eb1b2338e591b0b0aaff /arch/s390/kernel/kprobes.c | |
| parent | 000619680c3714020ce9db17eef6a4a7ce2dc28b (diff) | |
| parent | f8788d86ab28f61f7b46eb6be375f8a726783636 (diff) | |
Merge tag 'v5.6-rc3' into sched/core, to pick up fixes and dependent patches
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'arch/s390/kernel/kprobes.c')
| -rw-r--r-- | arch/s390/kernel/kprobes.c | 61 |
1 files changed, 5 insertions, 56 deletions
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index 6f1388391620..548d0ea9808d 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -56,21 +56,10 @@ struct kprobe_insn_cache kprobe_s390_insn_slots = { static void copy_instruction(struct kprobe *p) { - unsigned long ip = (unsigned long) p->addr; s64 disp, new_disp; u64 addr, new_addr; - if (ftrace_location(ip) == ip) { - /* - * If kprobes patches the instruction that is morphed by - * ftrace make sure that kprobes always sees the branch - * "jg .+24" that skips the mcount block or the "brcl 0,0" - * in case of hotpatch. - */ - ftrace_generate_nop_insn((struct ftrace_insn *)p->ainsn.insn); - p->ainsn.is_ftrace_insn = 1; - } else - memcpy(p->ainsn.insn, p->addr, insn_length(*p->addr >> 8)); + memcpy(p->ainsn.insn, p->addr, insn_length(*p->addr >> 8)); p->opcode = p->ainsn.insn[0]; if (!probe_is_insn_relative_long(p->ainsn.insn)) return; @@ -136,11 +125,6 @@ int arch_prepare_kprobe(struct kprobe *p) } NOKPROBE_SYMBOL(arch_prepare_kprobe); -int arch_check_ftrace_location(struct kprobe *p) -{ - return 0; -} - struct swap_insn_args { struct kprobe *p; unsigned int arm_kprobe : 1; @@ -149,28 +133,11 @@ struct swap_insn_args { static int swap_instruction(void *data) { struct swap_insn_args *args = data; - struct ftrace_insn new_insn, *insn; struct kprobe *p = args->p; - size_t len; - - new_insn.opc = args->arm_kprobe ? BREAKPOINT_INSTRUCTION : p->opcode; - len = sizeof(new_insn.opc); - if (!p->ainsn.is_ftrace_insn) - goto skip_ftrace; - len = sizeof(new_insn); - insn = (struct ftrace_insn *) p->addr; - if (args->arm_kprobe) { - if (is_ftrace_nop(insn)) - new_insn.disp = KPROBE_ON_FTRACE_NOP; - else - new_insn.disp = KPROBE_ON_FTRACE_CALL; - } else { - ftrace_generate_call_insn(&new_insn, (unsigned long)p->addr); - if (insn->disp == KPROBE_ON_FTRACE_NOP) - ftrace_generate_nop_insn(&new_insn); - } -skip_ftrace: - s390_kernel_write(p->addr, &new_insn, len); + u16 opc; + + opc = args->arm_kprobe ? BREAKPOINT_INSTRUCTION : p->opcode; + s390_kernel_write(p->addr, &opc, sizeof(opc)); return 0; } NOKPROBE_SYMBOL(swap_instruction); @@ -464,24 +431,6 @@ static void resume_execution(struct kprobe *p, struct pt_regs *regs) unsigned long ip = regs->psw.addr; int fixup = probe_get_fixup_type(p->ainsn.insn); - /* Check if the kprobes location is an enabled ftrace caller */ - if (p->ainsn.is_ftrace_insn) { - struct ftrace_insn *insn = (struct ftrace_insn *) p->addr; - struct ftrace_insn call_insn; - - ftrace_generate_call_insn(&call_insn, (unsigned long) p->addr); - /* - * A kprobe on an enabled ftrace call site actually single - * stepped an unconditional branch (ftrace nop equivalent). - * Now we need to fixup things and pretend that a brasl r0,... - * was executed instead. - */ - if (insn->disp == KPROBE_ON_FTRACE_CALL) { - ip += call_insn.disp * 2 - MCOUNT_INSN_SIZE; - regs->gprs[0] = (unsigned long)p->addr + sizeof(*insn); - } - } - if (fixup & FIXUP_PSW_NORMAL) ip += (unsigned long) p->addr - (unsigned long) p->ainsn.insn; |