| Message ID | 152812783350.10068.4690566636762511152.stgit@devbox (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | None | expand |
Masami Hiramatsu wrote: > Don't call the ->break_handler() from the arm kprobes code, ^^^ powerpc > because it was only used by jprobes which got removed. > > This also makes skip_singlestep() a static function since > only ftrace-kprobe.c is using this function. > > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Cc: Paul Mackerras <paulus@samba.org> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> > Cc: linuxppc-dev@lists.ozlabs.org > --- > arch/powerpc/include/asm/kprobes.h | 10 ---------- > arch/powerpc/kernel/kprobes-ftrace.c | 16 +++------------- > arch/powerpc/kernel/kprobes.c | 31 +++++++++++-------------------- > 3 files changed, 14 insertions(+), 43 deletions(-) With 2 small comments... Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> - Naveen > > diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h > index 674036db558b..785c464b6588 100644 > --- a/arch/powerpc/include/asm/kprobes.h > +++ b/arch/powerpc/include/asm/kprobes.h > @@ -102,16 +102,6 @@ extern int kprobe_exceptions_notify(struct notifier_block *self, > 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 skip_singlestep(struct kprobe *p, struct pt_regs *regs, > - struct kprobe_ctlblk *kcb); > -#else > -static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > - struct kprobe_ctlblk *kcb) > -{ > - return 0; > -} > -#endif > #else > static inline int kprobe_handler(struct pt_regs *regs) { return 0; } > static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; } > diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c > index 1b316331c2d9..3869b0e5d5c7 100644 > --- a/arch/powerpc/kernel/kprobes-ftrace.c > +++ b/arch/powerpc/kernel/kprobes-ftrace.c > @@ -26,8 +26,8 @@ > #include <linux/ftrace.h> > > static nokprobe_inline > -int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, > - struct kprobe_ctlblk *kcb, unsigned long orig_nip) > +int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > + struct kprobe_ctlblk *kcb, unsigned long orig_nip) > { > /* > * Emulate singlestep (and also recover regs->nip) > @@ -44,16 +44,6 @@ int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, > return 1; > } > > -int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > - struct kprobe_ctlblk *kcb) > -{ > - if (kprobe_ftrace(p)) > - return __skip_singlestep(p, regs, kcb, 0); > - else > - return 0; > -} > -NOKPROBE_SYMBOL(skip_singlestep); > - > /* Ftrace callback handler for kprobes */ > void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, > struct ftrace_ops *ops, struct pt_regs *regs) > @@ -82,7 +72,7 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, > __this_cpu_write(current_kprobe, p); > kcb->kprobe_status = KPROBE_HIT_ACTIVE; > if (!p->pre_handler || !p->pre_handler(p, regs)) > - __skip_singlestep(p, regs, kcb, orig_nip); > + skip_singlestep(p, regs, kcb, orig_nip); We can probably get rid of skip_singlestep() completely along with orig_nip since instructions are always 4 bytes on powerpc. So, the changes we do to nip should help to recover the value automatically. - Naveen
On Thu, 07 Jun 2018 17:07:00 +0530 "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote: > Masami Hiramatsu wrote: > > Don't call the ->break_handler() from the arm kprobes code, > ^^^ powerpc > > > because it was only used by jprobes which got removed. > > > > This also makes skip_singlestep() a static function since > > only ftrace-kprobe.c is using this function. > > > > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> > > Cc: Paul Mackerras <paulus@samba.org> > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> > > Cc: linuxppc-dev@lists.ozlabs.org > > --- > > arch/powerpc/include/asm/kprobes.h | 10 ---------- > > arch/powerpc/kernel/kprobes-ftrace.c | 16 +++------------- > > arch/powerpc/kernel/kprobes.c | 31 +++++++++++-------------------- > > 3 files changed, 14 insertions(+), 43 deletions(-) > > With 2 small comments... 2 ? or 1 ? > Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> > > - Naveen > > > > > diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h > > index 674036db558b..785c464b6588 100644 > > --- a/arch/powerpc/include/asm/kprobes.h > > +++ b/arch/powerpc/include/asm/kprobes.h > > @@ -102,16 +102,6 @@ extern int kprobe_exceptions_notify(struct notifier_block *self, > > 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 skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > - struct kprobe_ctlblk *kcb); > > -#else > > -static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > - struct kprobe_ctlblk *kcb) > > -{ > > - return 0; > > -} > > -#endif > > #else > > static inline int kprobe_handler(struct pt_regs *regs) { return 0; } > > static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; } > > diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c > > index 1b316331c2d9..3869b0e5d5c7 100644 > > --- a/arch/powerpc/kernel/kprobes-ftrace.c > > +++ b/arch/powerpc/kernel/kprobes-ftrace.c > > @@ -26,8 +26,8 @@ > > #include <linux/ftrace.h> > > > > static nokprobe_inline > > -int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > - struct kprobe_ctlblk *kcb, unsigned long orig_nip) > > +int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > + struct kprobe_ctlblk *kcb, unsigned long orig_nip) > > { > > /* > > * Emulate singlestep (and also recover regs->nip) > > @@ -44,16 +44,6 @@ int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > return 1; > > } > > > > -int skip_singlestep(struct kprobe *p, struct pt_regs *regs, > > - struct kprobe_ctlblk *kcb) > > -{ > > - if (kprobe_ftrace(p)) > > - return __skip_singlestep(p, regs, kcb, 0); > > - else > > - return 0; > > -} > > -NOKPROBE_SYMBOL(skip_singlestep); > > - > > /* Ftrace callback handler for kprobes */ > > void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, > > struct ftrace_ops *ops, struct pt_regs *regs) > > @@ -82,7 +72,7 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, > > __this_cpu_write(current_kprobe, p); > > kcb->kprobe_status = KPROBE_HIT_ACTIVE; > > if (!p->pre_handler || !p->pre_handler(p, regs)) > > - __skip_singlestep(p, regs, kcb, orig_nip); > > + skip_singlestep(p, regs, kcb, orig_nip); > > We can probably get rid of skip_singlestep() completely along with > orig_nip since instructions are always 4 bytes on powerpc. So, the > changes we do to nip should help to recover the value automatically. Good point! Yes, skip_singlestep() is no more exported, so we just consolidate it into kprobe_ftrace_handler() for simplifying operation. Thank you! > > - Naveen > >
Masami Hiramatsu wrote: > On Thu, 07 Jun 2018 17:07:00 +0530 > "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote: > >> Masami Hiramatsu wrote: >> > Don't call the ->break_handler() from the arm kprobes code, >> ^^^ powerpc >> >> > because it was only used by jprobes which got removed. >> > >> > This also makes skip_singlestep() a static function since >> > only ftrace-kprobe.c is using this function. >> > >> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> >> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> >> > Cc: Paul Mackerras <paulus@samba.org> >> > Cc: Michael Ellerman <mpe@ellerman.id.au> >> > Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> >> > Cc: linuxppc-dev@lists.ozlabs.org >> > --- >> > arch/powerpc/include/asm/kprobes.h | 10 ---------- >> > arch/powerpc/kernel/kprobes-ftrace.c | 16 +++------------- >> > arch/powerpc/kernel/kprobes.c | 31 +++++++++++-------------------- >> > 3 files changed, 14 insertions(+), 43 deletions(-) >> >> With 2 small comments... > > 2 ? or 1 ? Two, with one in the commit log above :) - Naveen
On Thu, 07 Jun 2018 22:07:26 +0530 "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote: > Masami Hiramatsu wrote: > > On Thu, 07 Jun 2018 17:07:00 +0530 > > "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote: > > > >> Masami Hiramatsu wrote: > >> > Don't call the ->break_handler() from the arm kprobes code, > >> ^^^ powerpc > >> > >> > because it was only used by jprobes which got removed. > >> > > >> > This also makes skip_singlestep() a static function since > >> > only ftrace-kprobe.c is using this function. > >> > > >> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > >> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> > >> > Cc: Paul Mackerras <paulus@samba.org> > >> > Cc: Michael Ellerman <mpe@ellerman.id.au> > >> > Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> > >> > Cc: linuxppc-dev@lists.ozlabs.org > >> > --- > >> > arch/powerpc/include/asm/kprobes.h | 10 ---------- > >> > arch/powerpc/kernel/kprobes-ftrace.c | 16 +++------------- > >> > arch/powerpc/kernel/kprobes.c | 31 +++++++++++-------------------- > >> > 3 files changed, 14 insertions(+), 43 deletions(-) > >> > >> With 2 small comments... > > > > 2 ? or 1 ? > > Two, with one in the commit log above :) Oops, sorry I missed it. yeah, the comment above is my mistake. I'll fix it. Thanks!
diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h index 674036db558b..785c464b6588 100644 --- a/arch/powerpc/include/asm/kprobes.h +++ b/arch/powerpc/include/asm/kprobes.h @@ -102,16 +102,6 @@ extern int kprobe_exceptions_notify(struct notifier_block *self, 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 skip_singlestep(struct kprobe *p, struct pt_regs *regs, - struct kprobe_ctlblk *kcb); -#else -static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs, - struct kprobe_ctlblk *kcb) -{ - return 0; -} -#endif #else static inline int kprobe_handler(struct pt_regs *regs) { return 0; } static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; } diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c index 1b316331c2d9..3869b0e5d5c7 100644 --- a/arch/powerpc/kernel/kprobes-ftrace.c +++ b/arch/powerpc/kernel/kprobes-ftrace.c @@ -26,8 +26,8 @@ #include <linux/ftrace.h> static nokprobe_inline -int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, - struct kprobe_ctlblk *kcb, unsigned long orig_nip) +int skip_singlestep(struct kprobe *p, struct pt_regs *regs, + struct kprobe_ctlblk *kcb, unsigned long orig_nip) { /* * Emulate singlestep (and also recover regs->nip) @@ -44,16 +44,6 @@ int __skip_singlestep(struct kprobe *p, struct pt_regs *regs, return 1; } -int skip_singlestep(struct kprobe *p, struct pt_regs *regs, - struct kprobe_ctlblk *kcb) -{ - if (kprobe_ftrace(p)) - return __skip_singlestep(p, regs, kcb, 0); - else - return 0; -} -NOKPROBE_SYMBOL(skip_singlestep); - /* Ftrace callback handler for kprobes */ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, struct ftrace_ops *ops, struct pt_regs *regs) @@ -82,7 +72,7 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, __this_cpu_write(current_kprobe, p); kcb->kprobe_status = KPROBE_HIT_ACTIVE; if (!p->pre_handler || !p->pre_handler(p, regs)) - __skip_singlestep(p, regs, kcb, orig_nip); + skip_singlestep(p, regs, kcb, orig_nip); else { /* * If pre_handler returns !0, it sets regs->nip and diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 600678fce0a8..f06747e2e70d 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -317,25 +317,17 @@ int kprobe_handler(struct pt_regs *regs) } prepare_singlestep(p, regs); return 1; - } else { - if (*addr != BREAKPOINT_INSTRUCTION) { - /* If trap variant, then it belongs not to us */ - kprobe_opcode_t cur_insn = *addr; - if (is_trap(cur_insn)) - goto no_kprobe; - /* The breakpoint instruction was removed by - * another cpu right after we hit, no further - * handling of this interrupt is appropriate - */ - ret = 1; + } else if (*addr != BREAKPOINT_INSTRUCTION) { + /* If trap variant, then it belongs not to us */ + kprobe_opcode_t cur_insn = *addr; + + if (is_trap(cur_insn)) goto no_kprobe; - } - p = __this_cpu_read(current_kprobe); - if (p->break_handler && p->break_handler(p, regs)) { - if (!skip_singlestep(p, regs, kcb)) - goto ss_probe; - ret = 1; - } + /* The breakpoint instruction was removed by + * another cpu right after we hit, no further + * handling of this interrupt is appropriate + */ + ret = 1; } goto no_kprobe; } @@ -350,7 +342,7 @@ int kprobe_handler(struct pt_regs *regs) */ kprobe_opcode_t cur_insn = *addr; if (is_trap(cur_insn)) - goto no_kprobe; + goto no_kprobe; /* * The breakpoint instruction was removed right * after we hit it. Another cpu has removed @@ -370,7 +362,6 @@ int kprobe_handler(struct pt_regs *regs) /* handler has already set things up, so skip ss setup */ return 1; -ss_probe: if (p->ainsn.boostable >= 0) { ret = try_to_emulate(p, regs);
Don't call the ->break_handler() from the arm kprobes code, because it was only used by jprobes which got removed. This also makes skip_singlestep() a static function since only ftrace-kprobe.c is using this function. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org --- arch/powerpc/include/asm/kprobes.h | 10 ---------- arch/powerpc/kernel/kprobes-ftrace.c | 16 +++------------- arch/powerpc/kernel/kprobes.c | 31 +++++++++++-------------------- 3 files changed, 14 insertions(+), 43 deletions(-)