icssg_hsr_h...lticast_sync(9)

💖 icssg_hsr_handle_multicast_sync 💖

okay bestie, welcome to the Kernel API Manual, section 9 — yes this is a kernel function page, and yes it's giving main character energy ✨ The whole thing lives at icssg_hsr_handle_multicast_sync(9), and honestly the name is lowkey a mouthful but we move 💅

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✨ NAME ✨

icssg_hsr_handle_multicast_sync — say it with me now: it handles HSR multicast overlapping memberships 🦋

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🌸 SYNOPSIS 🌸

void icssg_hsr_handle_multicast_sync (struct prueth_emac *emac );

that's it. that's the whole signature. no cap 🙈

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🎀 ARGUMENTS 🎀

• emac — the PRUETH EMAC private structure 💖 like, the lil private home where all the emac's stuff lives. that's the one thing you gotta hand over.

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🧚 DESCRIPTION 🧚

so here's the vibe: this function is the post-processor for multicast addresses, and it's specifically here to deal with the messy situation where the same address gets added from multiple paths — the example the page gives is hsr0 + eth1, iykyk 👑

and here's the plot twist that makes this function necessary: the kernel increments the refcount without triggering callbacks 😭 so nobody tells you when it happens. rude, honestly.

so instead of waiting for a callback that is literally never coming, this function goes and manually checks the refcount to detect what happened, then updates the FDB port membership to match. detective behaviour fr fr 🕵️‍♀️✨

ngl bestie, the whole point is: no callbacks = you gotta check the refcount yourself. don't miss that part 💀

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🦋 SEE ALSO 🦋

like a true bestie, this page brought its whole friend group 🫶

• the kernel file it lives in: ./drivers/net/ethernet/ti/icssg/icssg_prueth.c
• icssg_is_addr_synced(9)
• icssg_hsr_fdb_update(9)
• icssg_prueth_hsr_fdb_add_del(9)
• emac_ndo_open(9)
• emac_ndo_stop(9)
• emac_ndo_set_rx_mode(9)
• emac_xdp_xmit(9)
• emac_xdp_setup(9)
• emac_ndo_bpf(9)
• icssg_mode_firmware_names(9)

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and that's the whole page, bestie 💜 this lil gem comes from ./drivers/net/ethernet/ti/icssg, dated October 2026, sitting pretty in the Kernel API Manual at section 9 — go forth and sync those multicast memberships, you absolute icon 🌈👑⭐