4 ms·

I’m going to predict that they release a new version for macOS that includes a bug fix for the latest generation of processors. It will fix inaccurate readings.

I’m going to predict that they release a new version for macOS that includes a bug fix for the latest generation of processors. It will fix inaccurate readings. The new version will “correctly” show the flat line instead of the spikes. Then again it could also just be related to reports of it causing some macs not to be able to reboot after install. The only fix was booting safe mode and manually removing the kernel extension.

simcop2387 8y ago
> Then again it could also just be related to reports of it causing some macs not to be able to reboot after install. The only fix was booting safe mode and manually removing the kernel extension. Yikes, If that's true I'd bet that's the case. A bad kext that prevents booting would be a horrible experience.
Tunecrew 8y ago
I believe that was fixed in the most recent Mac version already - see the devs comments on the page. I have it installed on my MBP and have had no issues.
- Tunecrew 8y ago
  bizarrely though they have pulled it for some reason.
deleted 8y ago
[deleted]
ebikelaw 8y ago
Why does this need to be a kernel extension? Is there really no access to MSRs in macos as shipped by Apple?
- simcop2387 8y ago
  Generally no, the instructions that get access to many MSRs are privileged since they can affect the way things execute.
  - ebikelaw 8y ago
    I understand they are privileged but the way Linux handles this feature seems acceptable.
    - annerajb 8y ago
      Why? MSR are not userspace registers. You don't want the userspace messing around with them either because they won't know 100% what they do. But more importantly for security.
    - simcop2387 8y ago
      Even Linux requires this be done in kernel space, it's a requirement set by the architecture that the instructions that access them are run as part of the kernel. This is just like OSX, no different at all.
      - ebikelaw 8y ago
        In Linux root can open, read, and write /dev/msr.
        simcop2387 8y ago
        I haven't seen a /dev/msr before, but there is /dev/cpu/*/msr [1] provided by a kernel module. So there is a generic interface for them, but it's still all happening in kernel space. It's also not loaded by default either because it can cause system panics and corruption. [1] http://man7.org/linux/man-pages/man4/msr.4.html http://man7.org/linux/man-pages/man4/msr.4.html

simcop2387 8y ago

> Then again it could also just be related to reports of it causing some macs not to be able to reboot after install. The only fix was booting safe mode and manually removing the kernel extension. Yikes, If that's true I'd bet that's the case. A bad kext that prevents booting would be a horrible experience.

Tunecrew 8y ago

I believe that was fixed in the most recent Mac version already - see the devs comments on the page. I have it installed on my MBP and have had no issues.

Tunecrew 8y ago
bizarrely though they have pulled it for some reason.

deleted 8y ago

[deleted]

ebikelaw 8y ago

Why does this need to be a kernel extension? Is there really no access to MSRs in macos as shipped by Apple?

simcop2387 8y ago
Generally no, the instructions that get access to many MSRs are privileged since they can affect the way things execute.
- ebikelaw 8y ago
  I understand they are privileged but the way Linux handles this feature seems acceptable.
  - annerajb 8y ago
    Why? MSR are not userspace registers. You don't want the userspace messing around with them either because they won't know 100% what they do. But more importantly for security.
  - simcop2387 8y ago
    Even Linux requires this be done in kernel space, it's a requirement set by the architecture that the instructions that access them are run as part of the kernel. This is just like OSX, no different at all.
    - ebikelaw 8y ago
      In Linux root can open, read, and write /dev/msr.
      - simcop2387 8y ago
        I haven't seen a /dev/msr before, but there is /dev/cpu/*/msr [1] provided by a kernel module. So there is a generic interface for them, but it's still all happening in kernel space. It's also not loaded by default either because it can cause system panics and corruption. [1] http://man7.org/linux/man-pages/man4/msr.4.html http://man7.org/linux/man-pages/man4/msr.4.html