| Message ID | 20230530133603.16934-1-Jonathan.Cameron@huawei.com |
|---|---|
| Headers | show |
| Series | QEMU CXL Provide mock CXL events and irq support | expand |
Hello, Jonathan
When during the test of qmps of CXL events like "cxl-inject-general-media-event",
I am confuesd about the argument "flags". According to "qapi/cxl.json" in qemu,
this argument represents "Event Record Flags" in Common Event Record Format.
However, it seems like the specific 'Event Record Severity' in this field can be
different from the value of 'Event Status' in "Event Status Register".
For instance (take an injection example in the coverlatter):
{ "execute": "cxl-inject-general-media-event",
"arguments": {
"path": "/machine/peripheral/cxl-mem0",
"log": "informational",
"flags": 1,
"dpa": 1000,
"descriptor": 3,
"type": 3,
"transaction-type": 192,
"channel": 3,
"device": 5,
"component-id": "iras mem"
}}
In my understanding, the 'Event Status' is informational and the
'Event Record Severity' is Warning event, which means these two arguments are
independent of each other. Is my understanding correct?
Many thanks
Yuquan
On Fri, 15 Mar 2024 09:52:28 +0800 Yuquan Wang <wangyuquan1236@phytium.com.cn> wrote: > Hello, Jonathan > > When during the test of qmps of CXL events like "cxl-inject-general-media-event", > I am confuesd about the argument "flags". According to "qapi/cxl.json" in qemu, > this argument represents "Event Record Flags" in Common Event Record Format. > However, it seems like the specific 'Event Record Severity' in this field can be > different from the value of 'Event Status' in "Event Status Register". > > For instance (take an injection example in the coverlatter): > > { "execute": "cxl-inject-general-media-event", > "arguments": { > "path": "/machine/peripheral/cxl-mem0", > "log": "informational", > "flags": 1, > "dpa": 1000, > "descriptor": 3, > "type": 3, > "transaction-type": 192, > "channel": 3, > "device": 5, > "component-id": "iras mem" > }} > > In my understanding, the 'Event Status' is informational and the > 'Event Record Severity' is Warning event, which means these two arguments are > independent of each other. Is my understanding correct? The event status registers dictates the notification path (which log). So I think that's "informational" here. Whereas flags is about the specific error. One case where they might be different is where the Related Event Record Handle is set. An error might be reported as 1) Several things that were non fatal (each with their own record) 2) In combination they result in a fatal situation (also has it's own record). The QEMU injection shouldn't restrict these combinations more than the spec does (which is not at all!). This same disconnect in error severity is seen in UEFI CPER records for example where there is a containing record with one severity field, but more specific parts of record can have lower (or in theory higher) severity. Jonathan > > Many thanks > Yuquan >
v9: A few remaining QMP documentation formatting fixes from Markus. Fingers crossed it's now clean! Based on: [PATCH v8 0/4] hw/cxl: Poison get, inject, clear Based on: Message-ID: 20230526170010.574-1-Jonathan.Cameron@huawei.com Updated cover letter from earlier versions: One challenge here is striking the right balance between lots of constraints in the injection code to enforce particular reserved bits etc by breaking out all the flags as individual parameters vs having a reasonably concise API. I think this set strikes the right balance but others may well disagree :) Note that Ira raised the question of whether we should be automatically establishing the volatile flag based on the Device Physical Address of the injected error. My proposal is to not do so for now, but to possibly revisit tightening the checking of injected errors in future. Whilst the volatile flag is straight forwards, some of the other flags that could be automatically set (or perhaps checked for validiaty) are much more complex. Adding verification at this stage would greatly increase the complexity of the patch + we are missing other elements that would interact with this. I'm not concerned about potential breaking of backwards compatibility if it only related to the injection of errors that make no sense for a real device. CXL Event records inform the OS of various CXL device events. Thus far CXL memory devices are emulated and therefore don't naturally generate events. Add an event infrastructure and mock event injection. Previous versions included a bulk insertion of lots of events. However, this series focuses on providing the ability to inject individual events through QMP. Only the General Media Event is included in this series as an example. Other events can be added pretty easily once the infrastructure is acceptable. In addition, this version updates the code to be in line with the specification based on discussions around the kernel patches. Injection examples; { "execute": "cxl-inject-general-media-event", "arguments": { "path": "/machine/peripheral/cxl-mem0", "log": "informational", "flags": 1, "dpa": 1000, "descriptor": 3, "type": 3, "transaction-type": 192, "channel": 3, "device": 5, "component-id": "iras mem" }} { "execute": "cxl-inject-dram-event", "arguments": { "path": "/machine/peripheral/cxl-mem0", "log": "informational", "flags": 1, "dpa": 1000, "descriptor": 3, "type": 3, "transaction-type": 192, "channel": 3, "rank": 17, "nibble-mask": 37421234, "bank-group": 7, "bank": 11, "row": 2, "column": 77, "correction-mask": [33, 44, 55, 66] }} { "execute": "cxl-inject-memory-module-event", "arguments": { "path": "/machine/peripheral/cxl-mem0", "log": "informational", "flags": 1, "type": 3, "health-status": 3, "media-status": 7, "additional-status": 33, "life-used": 30, "temperature": -15, "dirty-shutdown-count": 4, "corrected-volatile-error-count": 3233, "corrected-persistent-error-count": 1300 }} Ira Weiny (4): hw/cxl/events: Add event status register hw/cxl/events: Wire up get/clear event mailbox commands hw/cxl/events: Add event interrupt support hw/cxl/events: Add injection of General Media Events Jonathan Cameron (3): hw/cxl: Move CXLRetCode definition to cxl_device.h hw/cxl/events: Add injection of DRAM events hw/cxl/events: Add injection of Memory Module Events qapi/cxl.json | 188 +++++++++++++++++++++++ include/hw/cxl/cxl_device.h | 80 +++++++++- include/hw/cxl/cxl_events.h | 168 +++++++++++++++++++++ hw/cxl/cxl-device-utils.c | 43 +++++- hw/cxl/cxl-events.c | 248 ++++++++++++++++++++++++++++++ hw/cxl/cxl-mailbox-utils.c | 166 ++++++++++++++------ hw/mem/cxl_type3.c | 292 +++++++++++++++++++++++++++++++++++- hw/mem/cxl_type3_stubs.c | 35 +++++ hw/cxl/meson.build | 1 + 9 files changed, 1165 insertions(+), 56 deletions(-) create mode 100644 include/hw/cxl/cxl_events.h create mode 100644 hw/cxl/cxl-events.c