ANNOUNCE: The following has been released:

trace-cmd 3.2.2

libtracefs 1.8.2

A ftrace selftest just failed due to the differences between bash and dash on how they interpret backslashes (\).

Bash will evaluate it once, where as dash will evaluate it every time.

i=123
TEST="\\$i"
echo "$TEST"

Bash will show: \123

where as dash will echo out the escape sequence of “123”.

A kprobe event self test needed to test the max number of arguments, where each argument held a backslash followed by a number. It created it with the loop:

   TEST_STRING=$1
   # Acceptable
   for i in `seq 1 $MAX_ARGS`; do
    TEST_STRING="$TEST_STRING \\$i"
   done
   echo "$TEST_STRING" >> dynamic_events

Which worked fine when /bin/sh was bash, but when /bin/sh was dash, it failed!

And checkbashisms did NOT catch it!

Just added tab completion for trace-cmd sqlhist for making synthetic events with the sql interface so much easier!

I’ve been wanting to add to trace-cmd start a way to make it start quicker. It’s currently slow because it resets most of tracefs before starting, and that can take seconds.

I forgot I already have this feature! trace-cmd set acts just like start, but it does not do the reset before starting. It’s very quick!

Note, it also does not re-enable tracing if it’s disabled. So you may want to run trace-cmd restart right after that, if that’s the case.

@vbabka @monsieuricon There’s nothing that says you can’t first create a bug in the mm system then follow it with the fix to give you kernel.org access. That would be a strong captcha!

@trini When I replied back saying that we are developers, I was thinking of adding, “but in the olden days, we had to wear asbestos suites to protect us from the flame wars”, but figured he wouldn’t get it.

@ptesarik @oleksandr
It's called the AsBestOS because it's the best OS!

Another email sent to the Linux Plumbers mailing list:

"Hi there,

This is Jacob Bryant and I came across the helpful information you shared on the lpc.events website and was wondering if you were open to adding new resources to your page.

Unfortunately, plumbers are at a higher risk of being diagnosed with mesothelioma, a rare cancer caused from exposure to asbestos that takes 20-50 years to develop. It’s extremely important that those who have and are working in plumbing are aware of this type of cancer. That's why we made a guide that covers everything you need to know about mesothelioma as a plumber."

@corruptian
🤣

From all the times Linus has yelled "Christ!" at my emails, I feel like I should become a missionary.

I received an email from my test suite that it failed while I was on the plane waiting for everyone to board. I ssh'd into my server with the Connect app, found it was a configuration issue, fixed the configuration and restarted the tests, before they closed the aircraft door!

@ptesarik @kernellogger @vbabka @workchronicles @hrw
With code and arrows pointing at the code I'm talking about.

@vbabka @kernellogger @hrw @workchronicles
I do one slide per bullet point

-Werror is great, until you need to debug an older kernel 😛

This meme perfectly describes pretty much every interaction between Linus Torvalds and myself!

I think this is the first time I ever used the quadratic equation for a real purpose since college! 🤔

https://lore.kernel.org/lkml/20250204172045.3a5d8d01@gandalf.local.home/

Not every day you can say you were complemented by Linus Torvalds saying you had an “interesting idea”. Always look for those silver linings!

https://lore.kernel.org/linux-trace-kernel/20241217131717.0fa5a21b@gandalf.local.home/T/#med0de149d3f7d1d4648406c277272ff6ea9eab04

Fixing up a messed up Debian upgrade where I needed to reinstall, I had to hit “Select this only if you know what you are doing”. I don’t know what I’m doing, but I had to hit it to do what I needed to get done 😛

Another useful email to the Linux Plumbers mailing list!

Kernel Recipes (which is always held in Paris) is thinking of changing their logo.