engine: retry NIC IP allocation instead of NPE when the allocation ra… - #14038
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nagaboinaramgopal wants to merge 1 commit into
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engine: retry NIC IP allocation instead of NPE when the allocation ra…#14038nagaboinaramgopal wants to merge 1 commit into
nagaboinaramgopal wants to merge 1 commit into
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DaanHoogland
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@nagaboinaramgopal can you see if this is applicable to older LTS branches?
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| // requested is null on the common "no explicit IP" deploy path. Guard it so losing the | ||
| // IP-allocation race retries the allocation instead of throwing a NullPointerException. |
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this comment is cluttering. can you move it to javadoc , possibly on a new method or remove it completely?
…ce is lost checkForRaceAndAllocateNic dereferenced the requested NicProfile when a concurrent deploy had already taken the IP (persistNicAfterRaceCheck returned null). On the common path the user requests no explicit IP, so requested is null and the loser threw a NullPointerException instead of nulling the IP and retrying. This defeats the ipv4AllocationRaceCheck retry for exactly the case it exists for (bulk/autoscale/CKS deploys onto one network). Null-guard the requested profile so the allocation is retried.
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Thanks @DaanHoogland . I removed the inline comment, the null-guard reads clearly on its own. And on the LTS question: the same deref of a possibly-null requested profile in checkForRaceAndAllocateNic is present on 4.19, 4.20 and 4.22, so this applies to all of them. Happy to open backport PRs once this merges, or to retarget to the oldest branch and let it merge forward, whichever you prefer. |
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Description
checkForRaceAndAllocateNic dereferenced the requested NicProfile when a
concurrent deploy had already taken the IP (persistNicAfterRaceCheck returned
null). On the common path the user requests no explicit IP, so requested is null
and the losing thread threw a NullPointerException instead of nulling the IP and
retrying. This defeats the ipv4AllocationRaceCheck retry for exactly the case it
was written for: many VMs deploying onto one guest network at once (bulk deploy,
autoscale groups, Kubernetes/CKS node provisioning).
Null-guard the requested profile so a lost race retries the allocation.
Types of changes
Feature/Enhancement Scale or Bug Severity
Bug Severity
How Has This Been Tested?
Added a unit test that simulates losing the allocation race with no explicit IP
requested and asserts the allocation is retried rather than throwing a
NullPointerException. Also built the standard packages and deployed on a KVM
advanced zone.