On Tuesday 13 January 2015 17:26:33 Al Stone wrote: > On 01/13/2015 10:22 AM, Grant Likely wrote: > > On Mon, Jan 12, 2015 at 7:40 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > >> On Monday 12 January 2015 12:00:31 Grant Likely wrote: > >>> RAS is also something where every company already has something that > >>> they are using on their x86 machines. Those interfaces are being > >>> ported over to the ARM platforms and will be equivalent to what they > >>> already do for x86. So, for example, an ARM server from DELL will use > >>> mostly the same RAS interfaces as an x86 server from DELL. > >> > >> Right, I'm still curious about what those are, in case we have to > >> add DT bindings for them as well. > > > > Certainly. > > In ACPI terms, the features used are called APEI (Advanced Platform > Error Interface), and defined in Section 18 of the specification. The > tables describe what the possible error sources are, where details about > the error are stored, and what to do when the errors occur. A lot of > the "RAS tools" out there that report and/or analyze error data rely on > this information being reported in the form given by the spec. > > I only put "RAS tools" in quotes because it is indeed a very loosely > defined term -- I've had everything from webmin to SNMP to ganglia, > nagios and Tivoli described to me as a RAS tool. In all of those cases, > however, the basic idea was to capture errors as they occur, and try to > manage them properly. That is, replace disks that seem to be heading > down hill, or look for faults in RAM, or dropped packets on LANs -- > anything that could help me avoid a catastrophic failure by doing some > preventive maintenance up front. > > And indeed a BMC is often used for handling errors in servers, or to > report errors out to something like nagios or ganglia. It could > also just be a log in a bit of NVRAM, too, with a little daemon that > reports back somewhere. But, this is why APEI is used: it tries to > provide a well defined interface between those reporting the error > (firmware, hardware, OS, ...) and those that need to act on the error > (the BMC, the OS, or even other bits of firmware). > > Does that help satisfy the curiosity a bit? Yes, it's much clearer now, thanks! Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
