5.4 KiB
NC-SI core dump
Author: DelphineCCChiu (Delphine_CC_Chiu@wiwynn.com)
Created: 03/12/2024
Problem Description
NIC core-dump is essential for NIC issue debugging, and it could be retrieved via both in-band and out of band method. The design here is providing the solution for NIC out of band dumping from BMC over NC-SI protocol.
Background and References
NC-SI command for dump retrieval: Reference: NC-SI spec v1.2: section: 8.4.114 https://www.dmtf.org/sites/default/files/standards/documents/DSP0222_1.2.0.pdf
NC-SI over MCTP: https://www.dmtf.org/sites/default/files/standards/documents/DSP0261_1.3.0.pdf
Requirements
This feature requires Linux kernel to support transferring new NC-SI command (0x4D) in net/ncsi module https://github.com/torvalds/linux/commits/master/net/ncsi
Proposed Design
Interface
This design will reuse existing phosphor-debug-collector module: https://github.com/openbmc/phosphor-debug-collector and extend the dump creation interface with a new "NC-SICoreDump" dump type.
The D-Bus interface for dump creation will be:"xyz.openbmc_project.Dump.Manager /xyz/openbmc_project/dump/bmc xyz.openbmc_project.Dump.Create"
To indicate which NC-SI link to target, The CreateDump method need one additional input parameter: "NICTarget". An EID or network interface, such as eth0 could be a valid value.
Dump Retrieval
Using standard NC-SI command: Retrieve Data From NC(0x4D) to get the dumps by NC-SI over RBT or NC-SI over MCTP protocol. All NC-SI dump procedure will be implemented in ncsi-netlink and ncsi-mctp utility in phosphor-networkd: https://github.com/openbmc/phosphor-networkd/blob/master/src/ncsi_netlink_main.cpp
Integrate with phosphor-debug-collector
Since phosphor-debug-collector using shell scripts for data collection, a new collector script named "ncsicoredump" will be added. This script will help to call ncsi-netlink or ncsi-mctp by different NICTarget and generate dump file under specific folder.
The following block diagram illustrate entire dump procedure and relationship between modules:
+----------------+ +-----------+
| | | |
-------------> Dump manager +-----------> DumpEntry |
CreateDump | | | |
+--------+-------+ +-----------+
|
|
|
+--------v-------+
| |
| Dreport |
| |
+--------+-------+
|
|
|
+--------v-------+
| |
| Plugin: +------------------+
| ncsicoredump | |
| | |
+--------+-------+ |
| |
| |
| |
| |
+------------+ +--------v-------+ +-------v------+ +------------+
| | | | | | | |
| DumpFile <-------+ NCSI-NetLink | | NCSI-MCTP +--------> DumpFile |
| | | | | | | |
+------------+ +--------^-------+ +-------^------+ +------------+
| |
--------------------------------+--------------------------+-----------------------------
Kernel |Netlink |MCTP
+--------v-------+ +--------v-------+
| | | |
|Net/NC-SI module| | I2C driver |
| | | |
+--------^-------+ +--------^-------+
| |
|NC-SI |SMBUS
| |
+--------v--------------------------v-------+
| |
| NIC |
| |
+-------------------------------------------+
Alternatives Considered
We shall block duplicated dump procedure by the reception ordering of NC-SI command(0x4d) shall be maintained. Since the core dump will contain up to 2 crash dump inside, we only support core dump now by it's sufficient for current usage.
Impacts
None.
Testing
Co-work with NIC vendor(Broadcom) for dump process/file validation.