UCT/IB/UD: ignore stale acks from before connection reset #11060
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Signed-off-by: Roie Danino <rdanino@nvidia.com>
Signed-off-by: Roie Danino <rdanino@nvidia.com>
gleon99
reviewed
Dec 15, 2025
src/uct/ib/ud/base/ud_ep.c
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| return; | ||
| } | ||
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| /* Ignore ACK for packets we never sent. This can happen if a stale ACK |
Contributor
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MInor: more concise.
e.g
/* Ignore stale ACKs for unsent packets (e.g., after endpoint reset).
* Valid ACK PSN must be in (acked_psn, psn). */
* */
test/gtest/uct/ib/test_ud.cc
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| #if UCT_UD_EP_DEBUG_HOOKS | ||
| /* Stale ACK PSN to inject - simulates ACK from before endpoint reset */ | ||
| static volatile uct_ud_psn_t stale_ack_psn_to_inject = 0; |
Contributor
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Minor. Maybe a better design approach would be to have stale_ack_psn_to_inject and inject_stale_ack_psn as class members, rather than static?
Can inherit and specify a sub-class.
Signed-off-by: Roie Danino <rdanino@nvidia.com>
…ed by tx hook Signed-off-by: Roie Danino <rdanino@nvidia.com>
evgeny-leksikov
approved these changes
Dec 17, 2025
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What
Ignore stale ACKs from previous connections in UD endpoint ACK processing.
Why
After an endpoint reset, stale ACKs from the previous connection can still arrive from the network. These ACKs reference PSNs that are no longer valid for the current connection, causing an assertion failure and crash.