On 8/31/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > Hi everyone: > > I am implemnting one ioctl() in one character device. > > That need know instruction pointer of user space. I am on i386 > platform. > I can sure I am in process context. and enter kernel by system call way. > > As I known, in default case, each task have one kernel stack, its length > is THREAD_SIZE(2 pages), and current_thread_info() is at its top. the > struct pt_regs is at bottom of this stack. > > so I write the code like here: > > pt_regs = ((struct pt_regs *)(THREAD_SIZE + current_thread_info()))+1;
try doing the following, I amnot sure of it, just try it. pt_regs = (struct pt_regs *) (((int *)(THREAD_SIZE + current)) - (sizeof(pt_regs) + 1)); > return pt_regs->eip; > > but it do not work! even, I get segment fault and kernel Oops at > sometime. > > Also, I am sure current_thread_info() return right value of current > user task. > > Any idea on here? > > thanks > > > sailor. > > > > > > > > > > > > - > 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/ > - 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/
