ARC/kprobes: Remove jprobe implementation

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

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Link: https://lore.kernel.org/lkml/152942436460.15209.3038881268172249579.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/arc/include/asm/kprobes.h b/arch/arc/include/asm/kprobes.h
index 2e52d18..2c1b479 100644 (file)
--- a/arch/arc/include/asm/kprobes.h
+++ b/arch/arc/include/asm/kprobes.h
@@ -45,8 +45,6 @@ struct prev_kprobe {
 
 struct kprobe_ctlblk {
        unsigned int kprobe_status;
-       struct pt_regs jprobe_saved_regs;
-       char jprobes_stack[MAX_STACK_SIZE];
        struct prev_kprobe prev_kprobe;
 };
 

diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c
index 42b0504..7811a6b 100644 (file)
--- a/arch/arc/kernel/kprobes.c
+++ b/arch/arc/kernel/kprobes.c
@@ -225,10 +225,8 @@ int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs)
 
                /* If we have no pre-handler or it returned 0, we continue with
                 * normal processing. If we have a pre-handler and it returned
-                * non-zero - which is expected from setjmp_pre_handler for
-                * jprobe, we return without single stepping and leave that to
-                * the break-handler which is invoked by a kprobe from
-                * jprobe_return
+                * non-zero - which means user handler setup registers to exit
+                * to another instruction, we must skip the single stepping.
                 */
                if (!p->pre_handler || !p->pre_handler(p, regs)) {
                        setup_singlestep(p, regs);
@@ -386,38 +384,6 @@ 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();
-       unsigned long sp_addr = regs->sp;
-
-       kcb->jprobe_saved_regs = *regs;
-       memcpy(kcb->jprobes_stack, (void *)sp_addr, MIN_STACK_SIZE(sp_addr));
-       regs->ret = (unsigned long)(jp->entry);
-
-       return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
-       __asm__ __volatile__("unimp_s");
-       return;
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-       struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-       unsigned long sp_addr;
-
-       *regs = kcb->jprobe_saved_regs;
-       sp_addr = regs->sp;
-       memcpy((void *)sp_addr, kcb->jprobes_stack, MIN_STACK_SIZE(sp_addr));
-       preempt_enable_no_resched();
-
-       return 1;
-}
-
 static void __used kretprobe_trampoline_holder(void)
 {
        __asm__ __volatile__(".global kretprobe_trampoline\n"