On 06/03/2015 02:53 PM, Timur Tabi wrote: > On 06/03/2015 01:25 PM, Guenter Roeck wrote: >> In general the idea here would be to use a crashdump kernel, which, >> when loaded, would reset the watchdog before it fires. This kernel >> would then write a core dump to a specified location. > > What is the mechanism for resetting the watchdog? The only code that > knows about the hardware registers is this driver. Does the crashdump > kernel call the watchdog stop function? > >> If arm64 doesn't support a crashdump kernel, it might still be possible >> to log the backtrace somewhere (eg in nvram using pstore if that is >> supported via acpi or efi).
Just to go back and explicitly answer this, arm64 does have support for crashdump, using the standard kexec/kdump approach, exactly as on x86. There's still some more work to be done to get the ACPI case fully upstream (e.g. on X-Gene platforms such as the HP ProLiant Moonshot m400 we need non-PSCI CPU parking protocol offlining when booting in UEFI/ACPI mode), but it's what we are doing in RHEL(SA) and the goal is to help clean up the remaining pieces upstream there. Jon. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
