unified logging corrupted

Issue persists up to today. Bug has been reported.

To recap:

The output of a kext using the unified logging via console or terminal is garbled after kextloading a rebuilt kext if another version was loaded before (macOS 10.12/10.13).

Steps to Reproduce:

build a kext with logging. kextload. rebuild it with slightly changed source. kextunload/kextload.

Anyone cares?

>Bug has been reported.

Be sure to add it to your thread for reference.

>Anyone cares?

Define 'anyone'...

Anyone cares?

I, for one, care. Alas, I don’t have any obvious suggestions for how to move forward here. My recommendation is that you open a DTS tech support incident and I, or one of my colleagues, can take a proper look at this.

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Thanks, opening an ADC incident was my first action. This resulted in requiring me opening a bug report: the place were eventually all issues get safely burried.

This resulted in requiring me opening a bug report

What is that bug number?

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Thanks, Quinn,

Apple bugreporter problem ID is 43176244 (as mentioned above).

Cheers,

Hagen.

Apple bugreporter problem ID is 43176244

Thanks.

It’s possible that this is tied to the UUID of your KEXT. When you reproduce the problem, does the new KEXT have a different UUID from the original one?

You can dump the KEXT’s UUID using:

$ otool -l /path/to/My.kext/Contents/MacOS/My | grep -B 1 -A 2 UUID
Load command 5
     cmd LC_UUID
 cmdsize 24
    uuid CF13567F-D968-3D1A-A71F-AABD0544F584

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Thanks,

yes the UUID changes.

Cheers,

Hagen.

Thanks. I updated your bug with that factoid (it’s in an internal area that you can’t see via Apple Bug Reporter).

Is your KEXT driving hardware? Or this is a software-only KEXT (VFS plug-in, NKE, virtual device, virus checker, and so on)?

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Yes, there are various kexts driving different hardware. For test purpose I also have software-only kexts. If it matters I could check the software-only kext for that behaviour.

Thanks,

Hagen.

Yes, there are various kexts driving different hardware.

OK, that rules out my other recommendation here )-: I avoid problems like this by doing all of my KEXT work in a VM. When I’m done with a particular debugging session, I simply revert the VM to a snapshot.

Alas, this isn’t feasible if you’re developing with real hardware.

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Since there is no progress here, is it possible to restart the logging process? Whats the name of the process?

Whats the name of the process?

That’d be

logd

I’ve no idea how safe it is to restart this, or indeed whether it’ll help.

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Thanks Quinn,

that seems to be true for Catalina (even for the man page - great, I am impressed...!!!), and there its named properly,

but not for Mojave (and unfortunately I am still bound to Mojave for some reasons like svn support, I still need Xcode 9 - while running current Xcode in parallel).

What would be the name of the unified logging process in Mojave?

Thanks & cheers,

Hagen.

I think the answer is still

logd

$ sw_vers
ProductName:    Mac OS X
ProductVersion: 10.14.6
BuildVersion:   18G95
$ sudo launchctl list | grep logd
40  0   com.apple.syslogd
58  0   com.apple.logd

Share and Enjoy
—
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"