[PATCH -tip v6 11/27] sh: kprobes: Remove jprobe implementation

Masami Hiramatsu
2018-06-19T16:09:57Z

Remove arch dependent setjump/longjump functions
and unused fields in kprobe_ctlblk for jprobes
from arch/sh.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: linux-sh@vger.kernel.org
---
arch/sh/include/asm/kprobes.h | 4 ---
arch/sh/kernel/kprobes.c | 51 -----------------------------------------
2 files changed, 55 deletions(-)

diff --git a/arch/sh/include/asm/kprobes.h b/arch/sh/include/asm/kprobes.h
index 85d8bcaa8493..6171682f7798 100644
--- a/arch/sh/include/asm/kprobes.h
+++ b/arch/sh/include/asm/kprobes.h
@@ -27,7 +27,6 @@ struct kprobe;

void arch_remove_kprobe(struct kprobe *);
void kretprobe_trampoline(void);
-void jprobe_return_end(void);

/* Architecture specific copy of original instruction*/
struct arch_specific_insn {
@@ -43,9 +42,6 @@ struct prev_kprobe {
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
- unsigned long jprobe_saved_r15;
- struct pt_regs jprobe_saved_regs;
- kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
struct prev_kprobe prev_kprobe;
};

diff --git a/arch/sh/kernel/kprobes.c b/arch/sh/kernel/kprobes.c
index 52a5e11247d1..2b5e58873b96 100644
--- a/arch/sh/kernel/kprobes.c
+++ b/arch/sh/kernel/kprobes.c
@@ -523,57 +523,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
return ret;
}

-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct jprobe *jp = container_of(p, struct jprobe, kp);
- unsigned long addr;
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
- kcb->jprobe_saved_regs = *regs;
- kcb->jprobe_saved_r15 = regs->regs[15];
- addr = kcb->jprobe_saved_r15;
-
- /*
- * TBD: As Linus pointed out, gcc assumes that the callee
- * owns the argument space and could overwrite it, e.g.
- * tailcall optimization. So, to be absolutely safe
- * we also save and restore enough stack bytes to cover
- * the argument area.
- */
- memcpy(kcb->jprobes_stack, (kprobe_opcode_t *) addr,
- MIN_STACK_SIZE(addr));
-
- regs->pc = (unsigned long)(jp->entry);
-
- return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
- asm volatile ("trapa #0x3a\n\t" "jprobe_return_end:\n\t" "nop\n\t");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
- unsigned long stack_addr = kcb->jprobe_saved_r15;
- u8 *addr = (u8 *)regs->pc;
-
- if ((addr >= (u8 *)jprobe_return) &&
- (addr <= (u8 *)jprobe_return_end)) {
- *regs = kcb->jprobe_saved_regs;
-
- memcpy((kprobe_opcode_t *)stack_addr, kcb->jprobes_stack,
- MIN_STACK_SIZE(stack_addr));
-
- kcb->kprobe_status = KPROBE_HIT_SS;
- preempt_enable_no_resched();
- return 1;
- }
-
- return 0;
-}
-
static struct kprobe trampoline_p = {
.addr = (kprobe_opcode_t *)&kretprobe_trampoline,
.pre_handler = trampoline_probe_handler