Earlier quoted context omitted.
We have discovered a critical bug in QNX 6 kernel in a networking scenario. There is no workaround, since the bug was in the core of their message passing infrastructure - a non-blocking by design kernel call, SendPulse(), sometimes blocks. It took me 9 months talking to them about this problem until I managed to reproduce it on just two nodes and half a page of code, and record kernel logs that clearly showed a race…
There is no safety-certified Linux. As far as I know there was no safety-certified QNX 6 either (QOS 1.0 was based on QNX 6.5 SP1, which is not the same as QNX 6 despite the numbers looking eerily similar). With a safety-certified system, you do not receive a patch because it violates the safety certification. Of course, you can get a patch and use it but then you're responsible for safety-certifying the entire stack…
They have incorporated the patch into some QNX 6.5 version, but we had to deliver the product long before they did this.