Messages in this thread | | | Date | Fri, 7 Sep 2007 15:58:05 +0530 | From | Ananth N Mavinakayanahalli <> | Subject | Re: [patch 06/10] Text Edit Lock - kprobes architecture independent support |
| |
On Thu, Sep 06, 2007 at 04:01:30PM -0400, Mathieu Desnoyers wrote:
<snip>
> @@ -716,8 +720,9 @@ static int __kprobes pre_handler_kretpro > struct kretprobe_instance, uflist); > ri->rp = rp; > ri->task = current; > + kernel_text_lock(); > arch_prepare_kretprobe(ri, regs); > - > + kernel_text_unlock();
pre_handler_kretprobe() is run when the entry probe for a retprobed function is hit and cannot block. You can't take a mutex here.
And why do we need to take the kernel_text_lock() here anyway? All arch_prepare_kretprobe() does is modify the return address stored either on stack or a register (arch specific) to the trampoline. We don't change any kernel text here.
Ananth - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |