vbg_core_open_session(9)

💖 vbg_core_open_session(9) 💖

okay so bestie, welcome to the Kernel API Manual ✨ this little cutie lives in vboxguest and it's literally the moment a new VBoxGuest user session is born. main character energy fr fr 🎀

---

✨ NAME ✨

vbg_core_open_session — creates a VBoxGuest user session. that's it, that's the whole vibe 🫶

---

🌸 SYNOPSIS 🌸

struct vbg_session * vbg_core_open_session (struct vbg_dev *gdev , u32
requestor );

like, you hand it a device and a requestor and it gives you back a whole session. slay 💅

---

🦋 ARGUMENTS 🦋

• gdev — the Guest extension device. the whole reason we're here, the icon 👑
• requestor — the VMMDEV_REQUESTOR_* flags. yes, all of them, with the literal asterisk, we don't make the rules 💀

---

🧚 DESCRIPTION 🧚

so vboxguest_linux.c calls this whenever userspace opens the char-device. that's the whole trigger. userspace opens the char-device → this bad boy runs. iykyk ✨

---

⭐ RETURN ⭐

it returns a pointer to the new session, or an ERR_PTR on error. so like… check it before you use it, bestie, no cap 🙈

lowkey important: ERR_PTR means it's an error dressed up as a pointer. use your IS_ERR/PTR_ERR besties, don't just dereference it 😭

---

🌈 SEE ALSO 🌈

• the kernel file ./drivers/virt/vboxguest/vboxguest_core.c — go read her, she's iconic
• vbg_guest_mappings_init(9)
• vbg_guest_mappings_exit(9)
• vbg_report_guest_info(9)
• vbg_report_driver_status(9)
• vbg_balloon_inflate(9)
• vbg_balloon_deflate(9)
• vbg_heartbeat_host_config(9)
• vbg_heartbeat_init(9)
• vbg_heartbeat_exit(9)
• vbg_track_bit_usage(9)
• vbg_reset_host_event_filter(9)
• vbg_set_session_event_filter(9)
• vbg_reset_host_capabilities(9)
• vbg_set_host_capabilities(9)
• vbg_acquire_session_capabilities(9)
• vbg_set_session_capabilities(9)
• vbg_query_host_version(9)
• vbg_core_init(9)
• vbg_core_exit(9)
• vbg_core_close_session(9)
• vbg_req_allowed(9)
• vbg_core_ioctl(9)
• vbg_core_set_mouse_status(9)

---

and that's the whole page, bestie 💜 this one's straight out of ./drivers/virt/vboxguest, dated October 2026, and the man page you just read is literally vbg_core_open_session(9). periodt 💅✨