Hi Kazu, On Wed, 19 Jun 2024 at 13:45, HAGIO KAZUHITO(萩尾 一仁) <k-hagio-ab@xxxxxxx> wrote: > > On 2024/06/06 3:10, Prasad Koya wrote: > > Hi > > > > We use makedumpfile to read the dmesg buffer from the vmcore. We are > > working on adding a feature to makedumpfile to extract the "process > > list" from /proc/vmcore. Our main use case is to save the processes > > that were running at the time of kernel crash to a file on the > > permanent storage from the kdump kernel. We intend to read a handful > > of useful data for each running task: pid, parent pid, real parent > > pid, priority, nice value, RSS, VM size, command, utime, stime, OOM > > score. > > > > Process list from vmcore can probably be read using crash utility, but > > in our embedded system using makedumpfile to do that job makes sense > > for us. > > > > If such an option is useful for the general users of makedumpfile, > > we'd like to get more inputs and contribute to this feature. > > Hi Prasad, > > thank you for sharing the idea. But sorry, currently we are not > interested in implementing such a big function in makedumpfile. > > The dmesg buffer is the most important information to be able to > determine the cause of a crash only with it, so the --dump-dmesg option > was implemented in makedumpfile first once upon a time. But now we have > handier vmcore-dmesg command in kexec-tools, so we don't intend to add > other functions to makedumpfile than making a dumpfile. > > I'm not sure whether these are doable, but I would suggest a few ideas > instead: > - make e.g. vmcore-process-list command like vmcore-dmesg. Not sure if this is worth either. I guess it can be done with some crash tool scripts or a crash plugin? > - use panic notifier to dump process list to the dmesg buffer before > kdump, and use vmcore-dmesg to get it. It is not recommended to add these before kdump if people still want a reliable kdump. > > Thanks, > Kazu > _______________________________________________ > kexec mailing list Thanks Dave > kexec@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/kexec > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
