Messages in this thread |  | | Date | Sun, 12 May 2024 20:50:24 +0000 | | From | "Dr. David Alan Gilbert" <> | | Subject | Re: Inquiry Regarding Handling of Kernel Crashes |
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* Muni Sekhar (munisekharrms@gmail.com) wrote: > Dear Linux Kernel Community,
Hi,
> I hope this email finds you well. I am currently engaged in testing > device drivers in Linux kernel mode, and I have encountered various > types of kernel crashes during my testing process. > > Among these, some examples of kernel crashes include OOPS, lockups and others. > > I have a few questions regarding the handling of kernel crashes during testing: > > When encountering a kernel crash during testing, is it advisable to > continue testing without rebooting the system? Or is it preferable to > reboot the system after each kernel crash and then resume testing?
Rebooting is best.
> Can the first kernel crash, whether it is an OOPS, or any other type > crash, potentially lead to subsequent crashes of the same or different > types? If so, should debugging efforts focus only on the first kernel > crash, or should all subsequent crashes also be considered and > addressed?
Yes - not all failures do that, but some will cause follow on crashes; looking at the first crash normally gives the most reliable idea of what went wrong. But keep all the logs, anything might help you figure it out.
> In the event that the system needs to be rebooted after a kernel > crash, how can user space test utilities be informed that a kernel > crash has occurred? Additionally, how can the system be configured to > automatically reboot in the event of a kernel crash?
See Documentation/admin-guide/kernel-parameters.txt there are quite a few useful ones, in particular: oops=panic will cause a panic after an oops which when you combine it with panic=30
means an oops will then cause a panic which causes a reboot.
You could also consider using a 'crash kernel' - on a panic that lands in a fresh kernel that just saves a memory snapshot that you can then try and debug.
Turning on a watchdog as well is good; some kernel bugs just hang rather than giving a nice oops.
> I would greatly appreciate any insights or best practices you can > share regarding the handling of kernel crashes during testing. Your > expertise and guidance on this matter would be invaluable to my > testing efforts. > > Thank you very much for your time and assistance. I look forward to > your response.
Good luck!
Dave
> > > -- > Thanks, > Sekhar > -- -----Open up your eyes, open up your mind, open up your code ------- / Dr. David Alan Gilbert | Running GNU/Linux | Happy \ \ dave @ treblig.org | | In Hex / \ _________________________|_____ http://www.treblig.org |_______/
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