Hello. On čtvrtek 8. září 2022 0:00:43 CEST Eric W. Biederman wrote: > Oleg Nesterov <oleg@xxxxxxxxxx> writes: > > > On 09/07, Oleksandr Natalenko wrote: > >> > >> The advantage of having CPU recorded in the file name is that > >> in case of multiple cores one can summarise them with a simple > >> ls+grep without invoking a fully-featured debugger to find out > >> whether the segfaults happened on the same CPU. > > > > Besides, if you only need to gather the statistics about the faulting > > CPU(s), you do not even need to actually dump the the core. For example, > > something like > > > > #!/usr/bin/sh > > > > echo $* >> path/to/coredump-stat.txt > > > > and > > echo '| path-to-script-above %C' >/proc/sys/kernel/core_pattern > > > > can help. > > So I am confused. I thought someone had modified print_fatal_signal > to print this information. Looking at the code now I don't see it, > but perhaps that is in linux-next somewhere. That's a different story that gets solved here: [1] [2]. [1] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/cpu&id=c926087eb38520b268515ae1a842db6db62554cc [2] https://lore.kernel.org/lkml/20220811024903.178925-1-ira.weiny@xxxxxxxxx/ > That would seem to be the really obvious place to put this and much > closer to the original fault so we ware more likely to record the > cpu on which things actually happened on. > > If we don't care about the core dump just getting the information in > syslog where it can be analyzed seems like the thing to do. > > For a developers box putting it in core pattern makes sense, isn't a > hinderance to use. For anyone else's box the information needs to come > out in a way that allows automated tools to look for a pattern. > Requiring someone to take an extra step to print the information seems > a hinderance to automated tools doing the looking. > > Eric > > -- Oleksandr Natalenko (post-factum) Principal Software Maintenance Engineer