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Bug Power Red Hat Software Linux

Linux Kernel Power Bug Is Fixed 145

An anonymous reader writes "The Linux kernel power bug that caused high power usage for many Intel Linux systems has finally been addressed. Matthew Garrett of Red Hat has devised a solution for the ASPM Linux power problem by mimicking Microsoft Windows' power behavior in the Linux kernel. A patch is on LKML for this solution to finally restore the battery life under Linux."
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Linux Kernel Power Bug Is Fixed

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  • Re:Good News (Score:2, Insightful)

    by CmdrPony ( 2505686 ) on Friday November 11, 2011 @05:25PM (#38029372)
    It's funny they had to fix it by copying the method from Windows though.
  • Re:Good News (Score:5, Insightful)

    by Anonymous Coward on Friday November 11, 2011 @05:28PM (#38029420)

    It's funny they had to fix it by copying the method from Windows though.

    Nothing funny here, if your hardware is optimized by the hardware manufacturer for windows, getting better performance from that hardware by mimicking windows behavior seems logical, if not controversial.

  • Re:Good News (Score:5, Insightful)

    by billcopc ( 196330 ) <> on Friday November 11, 2011 @05:37PM (#38029520) Homepage

    I don't find it funny, just common sense. It sounds like ASPM is very poorly documented, so if Windows is doing a decent job of implementing the functionality, then reverse-engineering, or at least guessing at how Windows does it, seems like a valid approach.

  • overblown (Score:2, Insightful)

    by markhahn ( 122033 ) on Friday November 11, 2011 @05:43PM (#38029588)

    this "issue" seemed to be mostly a traffic-getting vehicle for phoronix.

  • Re:Good News (Score:5, Insightful)

    by Nerdfest ( 867930 ) on Friday November 11, 2011 @05:44PM (#38029596)
    ... especially since the hardware manufacturers frequently deviate from the specifications in the standards to support Microsoft operating systems.
  • Re:Good News (Score:5, Insightful)

    by amiga3D ( 567632 ) on Friday November 11, 2011 @05:51PM (#38029678)

    I think it's more a case of the manufacturers supporting windows than the other way around. Of course Linux doesn't get that level of support because of the lower user base. Apple solves the problem by making their own hardware.

  • Re:This can't be! (Score:1, Insightful)

    by Anonymous Coward on Friday November 11, 2011 @06:12PM (#38029906)

    Surely it's not the manufactures fault for ignoring the standards they claim to support. It must be up to the OS developers to figure out what parts of the hardware are broken. /sarcasm

    This isn't a Linux bug fix. It's a workaround in Linux for hardware bugs. It's just as broken on Windows it's just that Windows doesn't use it.

    Bad Windows + Bad hardware = Linux's fault? Clearly everyone should emulate the defective behavior and employ reverse engineering to figure out just what that defective behavior just might be? This just another example of the destructive influence of the Windows monoculture.

    The only lameness here is the BROKEN HARDWARE happens to work on Windows.

    Do you know why broken RAM modules work on Linux? The user can tel Linux not to use the part of RAM with the stuck bits. Do you know why broken RAM modules work on Windows? Because everyone assumes the random lock ups is just Windows' normal behavior. The result? RAM sticks don't get sent back to the manufacture and everyone not running Windows has to put up with how shitty hardware has become just because it's "normal" for Windows fuck up. But try to tell that to a Wintard like you.

    Eat shit and die. (I see you have the first part down. Move on to step two--quickly.)

  • Re:Good News (Score:5, Insightful)

    by NotBorg ( 829820 ) on Friday November 11, 2011 @06:43PM (#38030268)
    What's the controversy? The [defective] hardware only works one way. It's just doing it the only one way that it works. You can't fault someone for going down the only path available.
  • Re:Good News (Score:5, Insightful)

    by Anonymous Coward on Friday November 11, 2011 @06:51PM (#38030346)

    Yes, because contributing a few open source project gives you the right to employ VERY proprietary methods and approaches to the vast majority of what you do. Filling baseless patent suits is perfectly acceptable so long as you have at least one open source project.

  • Re:Good News (Score:4, Insightful)

    by Martin Blank ( 154261 ) on Friday November 11, 2011 @07:15PM (#38030578) Homepage Journal

    Garrett was also in large part responsible for fixing a running problem [] with booting on UEFI systems, particularly notebooks. (That wasn't the only patch that needed to be written, but it did provide the foundation. It's also one of the funniest developer commentaries for a patch I've ever seen.) I've seen his name attached to Linux development for a while, but it's only recently that I've come to understand just how much of the deep internal architecture he understands and has helped to fix.

  • by jedidiah ( 1196 ) on Friday November 11, 2011 @10:12PM (#38031916) Homepage

    No. Battery life goes from 8hrs to 5hrs because Linux is actually "following the spec".

    Hacks and reverse engineering should not be necessary.

    The fact that this kind of nonsense still goes on in 2011 is not a black eye for Linux really. Although that's certainly what Microsoft intends. The clueless will certainly oblige them.

  • by caseih ( 160668 ) on Saturday November 12, 2011 @12:10AM (#38032518)

    Be that as it may, things appear to work fine on Windows. On Linux they don't. Hence the problem is Linux's problem. It's unfortunate that we have to work around boneheaded hardware and Microsoft's insistence on not documenting anything publicly. However that's the way things are. We can complain all we want about hardware manufacturers doing things wrong, but unless we can convince them to fix it (and 1% of their users whining about something that works just fine in Windows is not likely to get anywhere), it's our problem. And it is, from the users' pov a regression in the kernel. Under 2.6.37 battery was fine, under 2.6.38 it wasn't. It doesn't matter that the old kernel was doing things wrong and maybe dangerously. A regression that corrects behavior but still gets things wrong (the end result) is still a regression.

    I would think that Red Hat understands this (and it seems they do as the developer who created the patch to fix the logic works for them), but in Fedora you still can't load custom DSTDT firmware tables so my laptop still requires me to press a key repeatedly to get through the bootup sequence. In the bug report the devs basically said, why should a normal user have to mess with this. It's not our fault anyway. The BIOS is buggy (which is true). But yet the problem from the user's POV is that it's Fedora's fault as it works fine in Windows.

Kill Ugly Processor Architectures - Karl Lehenbauer