Messages in this thread | | | Date | Tue, 27 Aug 2013 21:03:32 +0900 | From | Masami Hiramatsu <> | Subject | Re: [PATCH 12/13] tracing/uprobes: Add more fetch functions |
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(2013/08/27 17:48), Namhyung Kim wrote: > From: Namhyung Kim <namhyung.kim@lge.com> > > Implement uprobe-specific stack and memory fetch functions and add > them to the uprobes_fetch_type_table. Other fetch fucntions will be > shared with kprobes. > > Original-patch-by: Hyeoncheol Lee <cheol.lee@lge.com> > Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> > Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> > Cc: Oleg Nesterov <oleg@redhat.com> > Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com> > Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> > Signed-off-by: Namhyung Kim <namhyung@kernel.org> > --- > kernel/trace/trace_probe.c | 9 ++- > kernel/trace/trace_probe.h | 1 + > kernel/trace/trace_uprobe.c | 188 +++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 192 insertions(+), 6 deletions(-) > > diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c > index eaee44d5d9d1..70cd3bfde5a6 100644 > --- a/kernel/trace/trace_probe.c > +++ b/kernel/trace/trace_probe.c > @@ -101,6 +101,10 @@ struct deref_fetch_param { > fetch_func_t fetch_size; > }; > > +/* > + * For uprobes, it'll get a vaddr from first call_fetch() so pass NULL > + * as a priv on the second dprm->fetch() not to translate it to vaddr again. > + */ > #define DEFINE_FETCH_deref(type) \ > __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ > void *data, void *dest, void *priv) \ > @@ -110,13 +114,14 @@ __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ > call_fetch(&dprm->orig, regs, &addr, priv); \ > if (addr) { \ > addr += dprm->offset; \ > - dprm->fetch(regs, (void *)addr, dest, priv); \ > + dprm->fetch(regs, (void *)addr, dest, NULL); \ > } else \ > *(type *)dest = 0; \ > } > DEFINE_BASIC_FETCH_FUNCS(deref) > DEFINE_FETCH_deref(string) > > +/* Same as above */ > __kprobes void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, > void *data, void *dest, void *priv) > { > @@ -126,7 +131,7 @@ __kprobes void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, > call_fetch(&dprm->orig, regs, &addr, priv); > if (addr && dprm->fetch_size) { > addr += dprm->offset; > - dprm->fetch_size(regs, (void *)addr, dest, priv); > + dprm->fetch_size(regs, (void *)addr, dest, NULL); > } else > *(string_size *)dest = 0; > } > diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h > index fc7edf3749ef..b1e7d722c354 100644 > --- a/kernel/trace/trace_probe.h > +++ b/kernel/trace/trace_probe.h > @@ -263,6 +263,7 @@ ASSIGN_FETCH_FUNC(bitfield, ftype), \ > #define NR_FETCH_TYPES 10 > > extern const struct fetch_type kprobes_fetch_type_table[]; > +extern const struct fetch_type uprobes_fetch_type_table[]; > > static inline __kprobes void call_fetch(struct fetch_param *fprm, > struct pt_regs *regs, void *dest, void *priv) > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c > index fc5f8aa62156..89d4b86abbe1 100644 > --- a/kernel/trace/trace_uprobe.c > +++ b/kernel/trace/trace_uprobe.c > @@ -530,6 +530,186 @@ static const struct file_operations uprobe_profile_ops = { > .release = seq_release, > }; > > +#ifdef CONFIG_STACK_GROWSUP > +static unsigned long adjust_stack_addr(unsigned long addr, unsigned n) > +{ > + return addr - (n * sizeof(long)); > +} > + > +static bool within_user_stack(struct vm_area_struct *vma, unsigned long addr, > + unsigned int n) > +{ > + return vma->vm_start <= adjust_stack_addr(addr, n); > +} > +#else > +static unsigned long adjust_stack_addr(unsigned long addr, unsigned n) > +{ > + return addr + (n * sizeof(long)); > +} > + > +static bool within_user_stack(struct vm_area_struct *vma, unsigned long addr, > + unsigned int n) > +{ > + return vma->vm_end >= adjust_stack_addr(addr, n); > +} > +#endif > + > +static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) > +{ > + struct vm_area_struct *vma; > + unsigned long addr = GET_USP(regs);
I recommend you to use user_stack_pointer() rather than GET_USP here. Since some arch seem not to have correct GET_USP implementation (e.g. arm), kernel build will be failed.
And at least trace_probe.c part is good for me.
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Thank you,
-- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com
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