[PATCH -tip v6 09/27] MIPS: kprobes: Remove jprobe implementation

Masami Hiramatsu
2018-06-19T16:08:59Z

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

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
---
arch/mips/include/asm/kprobes.h | 13 -----------
arch/mips/kernel/kprobes.c | 45 ---------------------------------------
2 files changed, 58 deletions(-)

diff --git a/arch/mips/include/asm/kprobes.h b/arch/mips/include/asm/kprobes.h
index ad1a99948f27..a72dfbf1babb 100644
--- a/arch/mips/include/asm/kprobes.h
+++ b/arch/mips/include/asm/kprobes.h
@@ -68,16 +68,6 @@ struct prev_kprobe {
unsigned long saved_epc;
};

-#define MAX_JPROBES_STACK_SIZE 128
-#define MAX_JPROBES_STACK_ADDR \
- (((unsigned long)current_thread_info()) + THREAD_SIZE - 32 - sizeof(struct pt_regs))
-
-#define MIN_JPROBES_STACK_SIZE(ADDR) \
- ((((ADDR) + MAX_JPROBES_STACK_SIZE) > MAX_JPROBES_STACK_ADDR) \
- ? MAX_JPROBES_STACK_ADDR - (ADDR) \
- : MAX_JPROBES_STACK_SIZE)
-
-
#define SKIP_DELAYSLOT 0x0001

/* per-cpu kprobe control block */
@@ -86,12 +76,9 @@ struct kprobe_ctlblk {
unsigned long kprobe_old_SR;
unsigned long kprobe_saved_SR;
unsigned long kprobe_saved_epc;
- unsigned long jprobe_saved_sp;
- struct pt_regs jprobe_saved_regs;
/* Per-thread fields, used while emulating branches */
unsigned long flags;
unsigned long target_epc;
- u8 jprobes_stack[MAX_JPROBES_STACK_SIZE];
struct prev_kprobe prev_kprobe;
};

diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c
index f5c8bce70db2..efdcd0b1ce12 100644
--- a/arch/mips/kernel/kprobes.c
+++ b/arch/mips/kernel/kprobes.c
@@ -468,51 +468,6 @@ 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);
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
- kcb->jprobe_saved_regs = *regs;
- kcb->jprobe_saved_sp = regs->regs[29];
-
- memcpy(kcb->jprobes_stack, (void *)kcb->jprobe_saved_sp,
- MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
-
- regs->cp0_epc = (unsigned long)(jp->entry);
-
- return 1;
-}
-
-/* Defined in the inline asm below. */
-void jprobe_return_end(void);
-
-void __kprobes jprobe_return(void)
-{
- /* Assembler quirk necessitates this '0,code' business. */
- asm volatile(
- "break 0,%0\n\t"
- ".globl jprobe_return_end\n"
- "jprobe_return_end:\n"
- : : "n" (BRK_KPROBE_BP) : "memory");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
- if (regs->cp0_epc >= (unsigned long)jprobe_return &&
- regs->cp0_epc <= (unsigned long)jprobe_return_end) {
- *regs = kcb->jprobe_saved_regs;
- memcpy((void *)kcb->jprobe_saved_sp, kcb->jprobes_stack,
- MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
- preempt_enable_no_resched();
-
- return 1;
- }
- return 0;
-}
-
/*
* Function return probe trampoline:
* - init_kprobes() establishes a probepoint here