On Mon, 23 Feb 2015 20:17:55 +0900, manty kuma said:

1. At the time of panic, many of pr_info prints are not flushed onto serial console. What can I do to get them(considering making them emerg is not an option)?

2. Is there a way I can flush the kernel buffer? I mean all the pending prints, if any, should be copied into kernel ring buffer.

In general, if your kernel is panic'ing, there really isn't much you can do, because your kernel is so messed up that it has declared any continued safe operation impossible. Even if the kernel oops'es, you still have a fighting chance of doing something, as long as it doesn't use a lock that the oopsed code was holding. With a panic, you don't even have that. If you're running with a EFI boot, you can enable saving the panic messages and the last bit of dmesg output to EFI nvram, and then recover it after rebooting from /sys/fs/pstore % zgrep PSTO /proc/config.gz CONFIG_EFI_VARS_PSTORE=y # CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE is not set CONFIG_PSTORE=y CONFIG_PSTORE_CONSOLE=y CONFIG_PSTORE_PMSG=y # CONFIG_PSTORE_FTRACE is not set CONFIG_PSTORE_RAM=y