Hi Dongjiu Geng, (versions of patches 1,2 and 4 have been queued by Catalin) (Nit 'ACPI / APEI:' is the normal subject prefix for ghes.c, this helps the maintainers know which patches they need to pay attention to when you are touching multiple trees) On 06/01/18 16:02, Dongjiu Geng wrote: > ARMv8.2 requires implementation of the RAS extension. > In > this extension, it adds SEI(SError Interrupt) notification > type, this patch adds new GHES error source SEI handling > functions. This reads as if this patch is handling SError RAS notifications generated by a CPU with the RAS extensions. These are about CPU->Software notifications. APEI and GHES are a firmware first mechanism which is Software->Software. Reading the v8.2 documents won't help anyone with the APEI/GHES code. Please describe this from the ACPI view, "ACPI 6.x adds support for NOTIFY_SEI as a GHES notification mechanism... ", its up to the arch code to spot a v8.2 RAS Error based on the cpu caps. > This error source parsing and handling method > is similar with the SEA. There are problems with doing this: Oct. 18, 2017, 10:26 a.m. James Morse wrote: | How do SEA and SEI interact? | | As far as I can see they can both interrupt each other, which isn't something | the single in_nmi() path in APEI can handle. I thinks we should fix this | first. [..] | SEA gets away with a lot of things because its synchronous. SEI isn't. Xie | XiuQi pointed to the memory_failure_queue() code. We can use this directly | from SEA, but not SEI. (what happens if an SError arrives while we are | queueing memory_failure work from an IRQ). | | The one that scares me is the trace-point reporting stuff. What happens if an | SError arrives while we are enabling a trace point? (these are static-keys | right?) | | I don't think we can just plumb SEI in like this and be done with it. | (I'm looking at teasing out the estatus cache code from being x86:NMI only. | This way we solve the same 'cant do this from NMI context' with the same | code'.) I will post what I've got for this estatus-cache thing as an RFC, its not ready to be considered yet. > Expose API ghes_notify_sei() to external users. External > modules can call this exposed API to parse APEI table and > handle the SEI notification. external modules? You mean called by the arch code when it gets this NOTIFY_SEI? Thanks, James -- 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
