On Wed, Aug 29, 2012 at 07:37:48PM +0200, Oleg Nesterov wrote: > On 08/22, Oleg Nesterov wrote: > > > > > Ehm. Is there anything I missed to do? Or are you speculating on > > > changes which will clash with these here? > > > > If we have task_set_blockstep(), then perhaps it mmakes sense to > > avoid user_enable_singlestep()/TIF_SINGLESTEP from the start. > > We will see. > > But it is not clear when we will have task_set_blockstep. > > So I am starting to think it would be better to apply your 1-2 and > change the code later. Still not correct, but better than nothing. > > > > But. The more I think about the current code, the more I dislike it. > And I am starting to think we do not need yet another "weak arch*" > hook for single-stepping. Yes, it was me who suggested it, but this > is because I didn't want to complicate the merging of powerpc port. > > However. > > Ananth, Sebastian, what if we start with the patch below? Then > we can change arch/x86/kernel/uprobes.c to use the static > uprobe_*_step() helpers from the 2nd patch.
In principle I am fine with the change. > If we agree this code should be per-arch, then why do need other > hooks? This is just ugly, we already have arch_pre/post_xol. > > The only problem is the pending powerpc patches, the change below > obviously breaks them. Were they already applied? If not, then > probably Ananth can do v6 on top of the patch below ;) The necessary > fixup is trivial. They are under review. I can do the change, but since this change is trivial enough, unless there is a pressing need to move the user_*_single_step() right away, can't we hold off till 3.6? This can be a simple enough cleanup then. If not, I can spin a v6.... Ananth -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
