[patch] add kdump_after_notifier
vgoyal at in.ibm.com
Fri Aug 17 06:56:30 EDT 2007
On Thu, Aug 16, 2007 at 06:26:35PM +0900, Takenori Nagano wrote:
> Vivek Goyal wrote:
> > So for the time being I think we can put RAS tools on die notifier list
> > and if it runs into issues we can always think of creating a separate list.
> > Few things come to mind.
> > - Why there is a separate panic_notifier_list? Can't it be merged with
> > die_chain? die_val already got one of the event type as PANIC. If there
> > are no specific reasons then we should merge the two lists. Registering
> > RAS tools on a single list is easier.
> I think it is difficult, because die_chain is defined by each architecture.
I think die_chain is arch independent definition (kernel/die_notifier.c)?
But anyway, to begin with it can be done only for panic_notifier.
> > - Modify Kdump to register on die_chain list.
> > - Modify Kdb to register on die_chain list.
> > - Export all the registered members of die_chain through sysfs along with
> > their priorities. Priorities should be modifiable. Most likely one
> > shall have to introduce additional field in struct notifier_block. This
> > field will be a string as an identifier of the user registerd. e.g
> > "Kdump", "Kdb" etc.
> > Now user will be able to view all the die_chain users through sysfs and
> > be able to modify the order in which these should run by modifying their
> > priority. Hence all the RAS tools can co-exist.
> This is my image of your proposal.
> - Print current order
> # cat /sys/class/misc/debug/panic_notifier_list
> priority name
> 1 IPMI
> 2 watchdog
> 3 Kdb
> 4 Kdump
I think Bernhard's suggestion looks better here. I noticed that
/sys/kernel/debug is already present. So how about following.
I think at some point of time we shall have to create another file say
Which can tell what does this tool do? Other a user might not have any
clue how to prioritize various things.
More information about the kexec