vmbus_sendpacket(9)

✨ NAME ✨

okay so bestie, welcome to vmbus_sendpacket(9) from the Kernel API Manual 💖. This one is literally about one job: send the specified buffer on the given channel. That’s it. That’s the whole assignment. Periodt.

🌸 SYNOPSIS 🌸

int vmbus_sendpacket (struct vmbus_channel *channel , void *buffer , u32
       bufferlen , u64 requestid , enum vmbus_packet_type type , u32 flags );

🎀 ARGUMENTS 🎀

• channel — pointer to a vmbus_channel structure. This is the channel bestie, the main character you’re sending on.
• buffer — pointer to the buffer you want to send the data from. Like, the data starts here.
• bufferlen — maximum size of what the buffer holds.
• requestid — identifier of the request.
• type — type of packet that is being sent, e.g. negotiate, time packet, etc. (iykyk)
• flags — 0 or VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED. Those are the options, no cap.

🦋 DESCRIPTION 🦋

So what it do? It sends the data in buffer directly to Hyper-V via the vmbus. And the key lore: it will send the data unparsed to Hyper-V. No filter, no remix, just the raw buffer vibes.

bestie, “unparsed” is the whole personality here — Hyper-V gets the data as-is. Don’t forget it. 💅

Mainly used by Hyper-V drivers. Slay.

🌈 SEE ALSO 🌈

Peep the kernel file ./drivers/hv/channel.c, plus these fellow icons:

• vmbus_free_buffer(9)
• vmbus_alloc_buffer(9)
• request_arr_init(9)
• vmbus_sendpacket_getid(9)
• __vmbus_recvpacket(9)

xoxo, source/version ./drivers/hv, date October 2026, and it’s giving vmbus_sendpacket(9) energy 🫶✨