An intermittent issue was first noticed on RHEL 8.x during kdump. When the dump completed and the system was in the process of resetting an NMI would get generated as a result of an IO error. For a discussion of the underlying cause and attempt to fix see: https://lkml.org/lkml/2019/12/25/159 The kernel's handling of the NMI generated an intermittent secondary NMI that would hang the system. As systemd enables WDT during shutdown, the WDT should have broken the system out of the hang, but hpwdt_pretimeout stops the WDT in order to allow the collection of a kdump. But as we are already in the crash kernel when the NMI is received, stopping the WDT is not necessary. Jerry Hoemann (2): watchdog/hpwdt: Disable NMI in Crash Kernel watchdog/hpwdt: Reflect changes drivers/watchdog/hpwdt.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) -- 1.8.3.1
