skiboot 5.9.3 was released on Wednesday November 22nd, 2017. It replaces skiboot-5.9.2 as the current stable release in the 5.9.x series.
Over skiboot-5.9.2, we have one NPU2/NVLink2 fix that causes the machine to crash hard in the event of hardware error rather than crash mysteriously later on whenever the NVLink2 links are used.
That fix is:
npu2: hw-procedures: Add check_credits procedure
As an immediate mitigator for a current hardware glitch, add a procedure that can be used to validate NTL credit values. This will be called as a safeguard to check that link training succeeded.
Assert that things are exactly as we expect, because if they aren’t, the system will experience a catastrophic failure shortly after the start of link traffic.