Add the new "weak" helper, arch_uretprobe_is_alive(), used by the next patches. It should return true if this return_instance is still valid. The arch agnostic version just always returns true.
The patch exports "struct return_instance" for the architectures which want to override this hook. We can also cleanup prepare_uretprobe() if we pass the new return_instance to arch_uretprobe_hijack_return_addr(). Signed-off-by: Oleg Nesterov <[email protected]> --- include/linux/uprobes.h | 10 ++++++++++ kernel/events/uprobes.c | 14 +++++--------- 2 files changed, 15 insertions(+), 9 deletions(-) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 60beb5d..50d2764 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -92,6 +92,15 @@ struct uprobe_task { unsigned int depth; }; +struct return_instance { + struct uprobe *uprobe; + unsigned long func; + unsigned long orig_ret_vaddr; /* original return address */ + bool chained; /* true, if instance is nested */ + + struct return_instance *next; /* keep as stack */ +}; + struct xol_area; struct uprobes_state { @@ -128,6 +137,7 @@ 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 arch_uretprobe_is_alive(struct return_instance *ret, struct pt_regs *regs); extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs); extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr, void *src, unsigned long len); diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 98e4d97..1c71b62 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -86,15 +86,6 @@ struct uprobe { struct arch_uprobe arch; }; -struct return_instance { - struct uprobe *uprobe; - unsigned long func; - unsigned long orig_ret_vaddr; /* original return address */ - bool chained; /* true, if instance is nested */ - - struct return_instance *next; /* keep as stack */ -}; - /* * Execute out of line area: anonymous executable mapping installed * by the probed task to execute the copy of the original instruction @@ -1818,6 +1809,11 @@ bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs) return false; } +bool __weak arch_uretprobe_is_alive(struct return_instance *ret, struct pt_regs *regs) +{ + return true; +} + /* * Run handler and ask thread to singlestep. * Ensure all non-fatal signals cannot interrupt thread while it singlesteps. -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
