On Fri, Aug 2, 2013 at 5:21 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > On Friday, August 02, 2013 04:31:37 PM Felipe Contreras wrote: >> On Fri, Aug 2, 2013 at 4:21 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: >> > On Friday, August 02, 2013 02:12:49 PM Felipe Contreras wrote: >> >> >> You forgot this patch: >> >> >> >> https://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit/?h=linux-next&id=3706231332d57072e0e2c0e59975443f3f18e673 >> >> >> >> Or do you think it's fine to boot these machines into a black screen? >> > >> > Seriously, what's wrong with you?! >> > >> > I didn't forget about it, I just didn't include it into this particular >> > pull request. >> > >> > And I'm not even sure I will push it for 3.11, because I prefer to revert >> > efaa14c for 3.11 if that's necessary to make your broken box work as before. >> >> The issue happens in more than just "my broken box", and yes, >> reverting that patch would help (in more than just my box), in the >> sense that at least Linux won't boot into a black screen. >> >> But the backlight control still wouldn't work, as it hasn't worked >> since v3.7, possibly in many ASUS laptops, for that you need more than >> just reverting efaa14c. > > Yes, last time it worked in 3.6 and in particular it doesn't work in 3.10. > My current goal is bring things back to the 3.10 state first, possibly without > introducing any new problems, because we're kind of late in the cycle. > That's better done by reverting stuff known to have introduced problems in > the first place and not by doing things that may introduce more of them. > > And your blacklisting patch has potential to introduce problems. Your goal is > to bring backlight control to the 3.6 state on that particular machine, but > the blacklist is done at the *system* level and very well may affect more > things than just backlight. You may not see any problems resulting from it > and you may not care even if there are some, but other users of it may use > different user space, for example, and may see problems that you're not seeing. > > That's why I'd very much prefer to do the revert at this point. Yes, that's fine, either the revert, or the patch I mentioned, or something else, but something has to be done, and it was better to do it in v3.11-rc4 than in v3.11-rc5, because that change itself can cause further problems. >> > Well, perhaps I just won't push it at all so that you actually can go and >> > complain to Linus about that ... >> >> That is very responsible from you. Screw the users, right? > > No, that's not my goal, sorry for disappointing you. > > The problem is that I'm not really convinced about the validity of the > blacklisting approach to begin with. As I said, the blacklisting is done > on the system level and the goal is to work around backlight control problems. > That sounds like a sledgehammer approach to me, which I don't really like. > If the blacklisting was more targeted, done at the video driver level etc., > I wouldn't really have any concerns about it, but that's not the case. > > And since people evidently could live for over 6 months with the backlight > control problems, maybe they'll survive some more time still and allow us to > find a better approach? They probably can survive without Linux at all, that doesn't mean we are doing our job. Let's do a though experiment, let's say you are right, and they can survive the 6 months it would take you to find the "perfect" solution, say in v3.13. What's wrong with having a partial solution in v3.12? If the blacklisting doesn't work properly (there's absolutely no evidence for that), then you revert it on v3.12.1. What's wrong with that approach? -- Felipe Contreras -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
