Re: [RFC PATCH -tip v5 07/27] powerpc/kprobes: Remove jprobe powerpc implementation

2018-06-07 Thread Masami Hiramatsu
On Thu, 07 Jun 2018 17:01:23 +0530
"Naveen N. Rao"  wrote:

> Masami Hiramatsu wrote:
> > Remove arch dependent setjump/longjump functions
> > and unused fields in kprobe_ctlblk for jprobes
> > from arch/powerpc. This also reverts commits
> > related __is_active_jprobe() function.
> > 
> > Signed-off-by: Masami Hiramatsu 
> > 
> > Cc: Benjamin Herrenschmidt 
> > Cc: Paul Mackerras 
> > Cc: Michael Ellerman 
> > Cc: "Naveen N. Rao" 
> > Cc: linuxppc-dev@lists.ozlabs.org
> > ---
> >  arch/powerpc/include/asm/kprobes.h |2 -
> >  arch/powerpc/kernel/kprobes-ftrace.c   |   15 ---
> >  arch/powerpc/kernel/kprobes.c  |   54 
> > 
> >  arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   39 ++---
> >  4 files changed, 5 insertions(+), 105 deletions(-)
> 
> LGTM.
> 
> Acked-by: Naveen N. Rao 

Thanks Naveen!

> 
> - Naveen
> 
> 


-- 
Masami Hiramatsu 


Re: [RFC PATCH -tip v5 07/27] powerpc/kprobes: Remove jprobe powerpc implementation

2018-06-07 Thread Naveen N. Rao

Masami Hiramatsu wrote:

Remove arch dependent setjump/longjump functions
and unused fields in kprobe_ctlblk for jprobes
from arch/powerpc. This also reverts commits
related __is_active_jprobe() function.

Signed-off-by: Masami Hiramatsu 

Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: "Naveen N. Rao" 
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/include/asm/kprobes.h |2 -
 arch/powerpc/kernel/kprobes-ftrace.c   |   15 ---
 arch/powerpc/kernel/kprobes.c  |   54 
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   39 ++---
 4 files changed, 5 insertions(+), 105 deletions(-)


LGTM.

Acked-by: Naveen N. Rao 

- Naveen




[RFC PATCH -tip v5 07/27] powerpc/kprobes: Remove jprobe powerpc implementation

2018-06-04 Thread Masami Hiramatsu
Remove arch dependent setjump/longjump functions
and unused fields in kprobe_ctlblk for jprobes
from arch/powerpc. This also reverts commits
related __is_active_jprobe() function.

Signed-off-by: Masami Hiramatsu 

Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: "Naveen N. Rao" 
Cc: linuxppc-dev@lists.ozlabs.org
---
 arch/powerpc/include/asm/kprobes.h |2 -
 arch/powerpc/kernel/kprobes-ftrace.c   |   15 ---
 arch/powerpc/kernel/kprobes.c  |   54 
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   39 ++---
 4 files changed, 5 insertions(+), 105 deletions(-)

diff --git a/arch/powerpc/include/asm/kprobes.h 
b/arch/powerpc/include/asm/kprobes.h
index 9f3be5c8a4a3..674036db558b 100644
--- a/arch/powerpc/include/asm/kprobes.h
+++ b/arch/powerpc/include/asm/kprobes.h
@@ -88,7 +88,6 @@ struct prev_kprobe {
 struct kprobe_ctlblk {
unsigned long kprobe_status;
unsigned long kprobe_saved_msr;
-   struct pt_regs jprobe_saved_regs;
struct prev_kprobe prev_kprobe;
 };
 
@@ -104,7 +103,6 @@ extern int kprobe_fault_handler(struct pt_regs *regs, int 
trapnr);
 extern int kprobe_handler(struct pt_regs *regs);
 extern int kprobe_post_handler(struct pt_regs *regs);
 #ifdef CONFIG_KPROBES_ON_FTRACE
-extern int __is_active_jprobe(unsigned long addr);
 extern int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
   struct kprobe_ctlblk *kcb);
 #else
diff --git a/arch/powerpc/kernel/kprobes-ftrace.c 
b/arch/powerpc/kernel/kprobes-ftrace.c
index 7a1f99f1b47f..1b316331c2d9 100644
--- a/arch/powerpc/kernel/kprobes-ftrace.c
+++ b/arch/powerpc/kernel/kprobes-ftrace.c
@@ -25,21 +25,6 @@
 #include 
 #include 
 
-/*
- * This is called from ftrace code after invoking registered handlers to
- * disambiguate regs->nip changes done by jprobes and livepatch. We check if
- * there is an active jprobe at the provided address (mcount location).
- */
-int __is_active_jprobe(unsigned long addr)
-{
-   if (!preemptible()) {
-   struct kprobe *p = raw_cpu_read(current_kprobe);
-   return (p && (unsigned long)p->addr == addr) ? 1 : 0;
-   }
-
-   return 0;
-}
-
 static nokprobe_inline
 int __skip_singlestep(struct kprobe *p, struct pt_regs *regs,
  struct kprobe_ctlblk *kcb, unsigned long orig_nip)
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index e4c5bf33970b..600678fce0a8 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -611,60 +611,6 @@ unsigned long arch_deref_entry_point(void *entry)
 }
 NOKPROBE_SYMBOL(arch_deref_entry_point);
 
-int 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();
-
-   memcpy(>jprobe_saved_regs, regs, sizeof(struct pt_regs));
-
-   /* setup return addr to the jprobe handler routine */
-   regs->nip = arch_deref_entry_point(jp->entry);
-#ifdef PPC64_ELF_ABI_v2
-   regs->gpr[12] = (unsigned long)jp->entry;
-#elif defined(PPC64_ELF_ABI_v1)
-   regs->gpr[2] = (unsigned long)(((func_descr_t *)jp->entry)->toc);
-#endif
-
-   /*
-* jprobes use jprobe_return() which skips the normal return
-* path of the function, and this messes up the accounting of the
-* function graph tracer.
-*
-* Pause function graph tracing while performing the jprobe function.
-*/
-   pause_graph_tracing();
-
-   return 1;
-}
-NOKPROBE_SYMBOL(setjmp_pre_handler);
-
-void __used jprobe_return(void)
-{
-   asm volatile("jprobe_return_trap:\n"
-"trap\n"
-::: "memory");
-}
-NOKPROBE_SYMBOL(jprobe_return);
-
-int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
-   struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
-   if (regs->nip != ppc_kallsyms_lookup_name("jprobe_return_trap")) {
-   pr_debug("longjmp_break_handler NIP (0x%lx) does not match 
jprobe_return_trap (0x%lx)\n",
-   regs->nip, 
ppc_kallsyms_lookup_name("jprobe_return_trap"));
-   return 0;
-   }
-
-   memcpy(regs, >jprobe_saved_regs, sizeof(struct pt_regs));
-   /* It's OK to start function graph tracing again */
-   unpause_graph_tracing();
-   preempt_enable_no_resched();
-   return 1;
-}
-NOKPROBE_SYMBOL(longjmp_break_handler);
-
 static struct kprobe trampoline_p = {
.addr = (kprobe_opcode_t *) _trampoline,
.pre_handler = trampoline_probe_handler
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S 
b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index 3f3e81852422..4e84a713e80a 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -99,39 +99,13 @@ ftrace_call:
bl