On Thu, Jan 28, 2021 at 3:01 PM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: > > Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> writes: > > > kmsg_dump(KMSG_DUMP_SHUTDOWN) is called before > > machine_restart(), machine_halt(), machine_power_off(), the only one that > > is missing is machine_kexec(). > > > > The dmesg output that it contains can be used to study the shutdown > > performance of both kernel and systemd during kexec reboot. > > > > Here is example of dmesg data collected after kexec: > > As long was we keep kmsg_dump out of the crash_kexec path where > it completely breaks kexec on panic this seems a reasonable thing to do. > On the ordinary kernel_kexec path everything is expected to be working. This is an ordinary kexec reboot path, not kdump. > > Is kmsg_dump expected to work after all of the device drivers > are shut down? Otherwise this placement of kmsg_dump is too late. Yes it is. It is called after device_shutdown(); in all other places. Thank you, Pasha _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
