Linux 5.17-rc2 Released - "A Bit On The Bigger Side"

[phoronix]

Phoronix: Linux 5.17-rc2 Released - "A Bit On The Bigger Side"

Linus Torvalds' schedule due to travels remains a bit off and as such Linux 5.17-rc2 is already available this morning...

https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.17-rc2

[cl333r]

Speaking of Linux in general, does it have an antivirus or something that kills processes? Maybe systemd does?
I'm launching a process as sudo from the terminal and it seems to get killed abruptly, what could it be?

I'm inserting printf("..\n") commands to trace where it's exiting, rebuilding the app and same thing happens, it doesn't even get to print the next printf() command, just exits for no reason. (The app does I/O in root folder).

Ubuntu 21.10

[nkalkhof]

I'm curious to see how big the impact of the latest i915 mitigations will be. Hopefully Michael will run some benchmarking soon....

[scratchi]

Speaking of Linux in general, does it have an antivirus or something that kills processes? Maybe systemd does?
I'm launching a process as sudo from the terminal and it seems to get killed abruptly, what could it be?

I'm inserting printf("..\n") commands to trace where it's exiting, rebuilding the app and same thing happens, it doesn't even get to print the next printf() command, just exits for no reason. (The app does I/O in root folder).

Ubuntu 21.10

Anything in logged in dmesg? Maybe there's a segfault?
Have you tried stepping through it with gdb? Maybe it can dump some traces if you can enable debug in your code?

No default AV in Linux/systemd or Ubuntu 21.10 that I know of, not out of the box. ClamAV and others exist, but you'd need to install them yourself.

[Danny3]

Did they left a way to turn these new mitigations off?

[cl333r]

Anything in logged in dmesg? Maybe there's a segfault?
Have you tried stepping through it with gdb? Maybe it can dump some traces if you can enable debug in your code?

No default AV in Linux/systemd or Ubuntu 21.10 that I know of, not out of the box. ClamAV and others exist, but you'd need to install them yourself.

Nothing in dmesg related to app crash, segfaults usually print something to the terminal like "segmentation fault", the app though exits cleanly at random points (no exit() called inside the app). It's weird, never happened to me before.

[nkalkhof]

Did they left a way to turn these new mitigations off?

According to the patchset it doesn't look like i915.mitigations=off covers that so it looks like everyone has to take it!

[scratchi]

Nothing in dmesg related to app crash, segfaults usually print something to the terminal like "segmentation fault", the app though exits cleanly at random points (no exit() called inside the app). It's weird, never happened to me before.

Ubuntu has apparmor, which is enabled by default. Can you try stop apparmor for a test?

sudo systemctl stop apparmor

If it works, then you can tweak apparmor config to allow you application without fully stopping/disabling it (or adjust your code so apparmor doesn't block it with default profile). I assume if that's the case, apparmor block should be logged somewhere, but it's been a while since I played with it.

Hope that helps, good luck!

[tildearrow]

Nothing in dmesg related to app crash, segfaults usually print something to the terminal like "segmentation fault", the app though exits cleanly at random points (no exit() called inside the app). It's weird, never happened to me before.

Try using strace, which will display system calls used by the application.

[OmniNegro]

ClamTK is what I use.

https://gitlab.com/dave_m/clamtk/-/wikis/Home