On 07/25/15 at 01:43pm, Minfei Huang wrote:
On 07/23/15 at 04:48pm, Dave Young wrote:
> We have added *wdt in kdump initramfs, but to improve it more we can do below
> (1) load wdt drivers as early as possible so that we can save time before wdt
timeout
> some drivers like iTCO_wdt can stop the watchdog while driver initialization,
so
> it can give more chance for kdump.
> It can save time especially in case some drivers take long time to init, like
> some storage and networking cards.
> (2) add only used wdt drivers in kdump initrd instead of add *wdt
> wdt driver layer need a change so that we can get the proper driver name from
> /dev/watchdog. Question to this is are we sure 1st kernel use /dev/watchdog
> instead of /dev/watchdog1? It need more investigation.
> (3) in case a driver can not stop (nowayout?) during module_init, we need load it
> as early as possible and kick the watchdog. Likely we can use systemd default
> watchdog functionality.
>
> This patch is about to address (1), and specially for iTCO_wdt, we only tested
> iTCO_wdt, thus in this patch only add this driver, need investigate on other
drivers
> later to see if other drivers works in this way.
>
Once we load the iTCO_wdt and lpc_ich module as earlier as possible, do
they have side effect for the 2nd kernel?
There's no side effect. Actually moving wdt other than iTCO to early phase is also
safe, just only tested iTCO.
Thanks
Dave