Hi, I'm seeing an issue where the iTCO_wdt module doesn't load with the below error, [ 3.827599] iTCO_wdt: Intel TCO WatchDog Timer Driver v1.11 [ 3.828440] iTCO_wdt iTCO_wdt: can't request region for resource [mem 0x00c5fffc-0x00c5ffff] [ 3.828803] iTCO_wdt: probe of iTCO_wdt failed with error -16 CPU and logs: cpu: Intel(R) Core(TM) i3-8100 CPU @ 3.60GHz dmesg logs: http://paste.debian.net/1092702/ lsmod output: https://paste.debian.net/1092703/ root@localhost:~# uname -a Linux localhost.localdomain 4.14.103-rt55 #1 SMP PREEMPT RT Tue Jul 23 03:53:28 UTC 2019 x86_64 GNU/Linux Please let me know if the error (can't request region for resource) is related to the patches below, https://patchwork.kernel.org/patch/9627085/ https://lore.kernel.org/patchwork/patch/770990/ I tested with the patch https://lore.kernel.org/patchwork/patch/770990/ and it fixes the issue. root@localhost:/home/vignesh# dmesg | grep wdt [ 5.766470] iTCO_wdt: Intel TCO WatchDog Timer Driver v1.11 [ 5.767104] iTCO_wdt: Found a Intel PCH TCO device (Version=4, TCOBASE=0x0400) [ 5.767865] iTCO_wdt: initialized. heartbeat=30 sec (nowayout=0) But the patch was not merged upstream. When testing the hardware watchdog, it doesn't trigger a reset even after triggering a sysrq crash. The system freezes and there is no reboot. I noticed the timeleft value is not getting updated. root@localhost:~# cat /sys/class/watchdog/watchdog0/timeleft 15 root@localhost:~# cat /sys/class/watchdog/watchdog0/timeleft 15 root@localhost:~# cat /sys/class/watchdog/watchdog0/timeleft 15 This issue has been discussed in below email thread, http://lkml.iu.edu/hypermail/linux/kernel/1609.1/01979.html https://lkml.org/lkml/2016/9/8/641 In another platform the hardware watchdog works. root@debian:~# dmesg | grep wdt [ 3.901842] iTCO_wdt: Intel TCO WatchDog Timer Driver v1.11 [ 3.903415] iTCO_wdt: Found a Intel PCH TCO device (Version=4, TCOBASE=0x0400) [ 3.937816] iTCO_wdt: initialized. heartbeat=30 sec (nowayout=0) CPU and logs cpu: Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz dmesg logs: http://paste.debian.net/1092845/ lsmod output: http://paste.debian.net/1092846/ root@debian:~# uname -a Linux debian 4.14.103-rt55 #1 SMP PREEMPT RT Tue Jul 23 03:53:28 UTC 2019 x86_64 GNU/Linux Hardware watchdog triggers a reset and the watchdog timer counter is started and the value gets updated. root@debian:~# cat /sys/class/watchdog/watchdog0/timeleft 13 root@debian:~# cat /sys/class/watchdog/watchdog0/timeleft 12 root@debian:~# cat /sys/class/watchdog/watchdog0/timeleft 11 root@debian:~# My questions: 1. Please let me know if it is okay to take https://lore.kernel.org/patchwork/patch/770990/ patch or will there be an update to the original patch? 2. Could the hardware watchdog not triggering a reset (timeleft value not getting updated) could be a hardware problem? Thanks. Regards, Vignesh
