3 ms·

I guess when the kernel panics, there is nothing to write the core dump for you...

• 2OEH8eoCRo0 4y ago
  kdump https://en.wikipedia.org/wiki/Kdump_(Linux) https://en.wikipedia.org/wiki/Kdump_(Linux) He also mentions that programs can report problems automatically to the distro devs. For example: https://retrace.fedoraproject.org/faf/problems/ https://retrace.fedoraproject.org/faf/problems/ A kernel dump is not something you always want to upload since it can be large and contain sensitive info. I'm not a kernel dev though.
• detaro 4y ago
  The kernel crash dump mechanism works by reserving some memory, which it boots a fresh copy of the kernel into on kernel panics, which then takes care of reading the old dead kernel from memory and saving the dump. Of course this working requires the fresh kernel to be able to get up and do that without itself crashing, so it can't capture every scenario. And it is bringing down the system completely, and there's lots of pros and cons to be argued about that vs attempting to continue or limp along.
  • yencabulator 4y ago
    The mechanism you describe is used/usable only in very specific scenarios. For practically all non-virtualized Linux hosts out there, the kernel crash dump mechanism works by adding ASCII text to kmesg, which is then read by journald, processed a little, and appended to a file -- which just means submitted back to the kernel for writing, which means FS needs to work, disk I/O needs to work, and so on.