lkml.org 
[lkml]   [2013]   [Nov]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 01/15] uprobes: allow ignoring of probe hits
On 11/26, David Long wrote:
>
> From: "David A. Long" <dave.long@linaro.org>
>
> Allow arches to decided to ignore a probe hit. ARM will use this to
> only call handlers if the conditions to execute a conditionally executed
> instruction are satisfied.
>
> Upleveled for v3.12-rc5.
>
> Signed-off-by: David A. Long <dave.long@linaro.org>

Acked-by: Oleg Nesterov <oleg@redhat.com>


> ---
> include/linux/uprobes.h | 1 +
> kernel/events/uprobes.c | 9 +++++++++
> 2 files changed, 10 insertions(+)
>
> diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
> index 319eae7..197a36e 100644
> --- a/include/linux/uprobes.h
> +++ b/include/linux/uprobes.h
> @@ -134,6 +134,7 @@ extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk);
> extern int arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data);
> extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
> extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs);
> +extern bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs);
> #else /* !CONFIG_UPROBES */
> struct uprobes_state {
> };
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 24b7d6c..4eec7ce 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -1778,6 +1778,11 @@ static bool handle_trampoline(struct pt_regs *regs)
> return true;
> }
>
> +bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs)
> +{
> + return false;
> +}
> +
> /*
> * Run handler and ask thread to singlestep.
> * Ensure all non-fatal signals cannot interrupt thread while it singlesteps.
> @@ -1828,7 +1833,11 @@ static void handle_swbp(struct pt_regs *regs)
> if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags)))
> goto out;
>
> + if (arch_uprobe_ignore(&uprobe->arch, regs))
> + goto out;
> +
> handler_chain(uprobe, regs);
> +
> if (can_skip_sstep(uprobe, regs))
> goto out;
>
> --
> 1.8.1.2
>



\
 
 \ /
  Last update: 2013-11-28 20:01    [W:0.151 / U:2.664 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site