2010/5/23 Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx>: > On Sun, May 23, 2010 at 09:44:20PM +0800, Ming Lei wrote: >> 2010/5/23 Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx>: >> >> ENTRY(ret_to_user) >> >> ret_slow_syscall: >> >> - disable_irq @ disable interrupts >> >> + disable_irq_notrace @ disable interrupts >> > >> > I think this one does need to be traced - the pending work functions are >> > all C code which could call back into lockdep. >> >> If there are pending works, schedule will be called to give cpu to it, >> I wonder why the work function to be scheduled will be run with irq >> disabled. Seems we should enable irq again before calling schedule, >> not sure. > > No. I'm talking about things like do_notify_resume(). > > I think the above should be left as-is, so that as far as lockdep is > concerned, IRQs are off while userspace runs. What happens between > returning to userspace and re-entering the kernel has no bearing what > so ever on lockdep. > Oh, trace_ret_hardirqs_on has to be added before returning to user-space to remove the warning, like x86 and mips. If you agree, I'd like to post a new version patch. Thanks, -- Lei Ming -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
