x86_spec_ctrl_restore_host(9)

🦋 x86_spec_ctrl_restore_host(9) — NAME 🦋

okay so bestie, this is x86_spec_ctrl_restore_host(9), straight out of the Kernel API Manual, and it does exactly what the name says: Restore host speculation control registers 💅✨

🌸 SYNOPSIS 🌸

void x86_spec_ctrl_restore_host (u64 guest_virt_spec_ctrl );

🎀 ARGUMENTS 🎀

• guest_virt_spec_ctrl — the guest-controlled bits of MSR_VIRT_SPEC_CTRL 👀 (and yes, those bits may get translated to MSR_AMD64_LS_CFG bits, iykyk).

✨ DESCRIPTION ✨

So the whole vibe here is: it avoids writing to the MSR if the content/bits are the same 🫶 no cap, it's doing a little vibe check first and skipping the write when nothing actually changed. iconic behavior, honestly 💖

🌈 SEE ALSO 🌈

• Kernel file ./arch/x86/include/asm/spec-ctrl.h 🧚
• x86_spec_ctrl_set_guest(9) ⭐

mwah 💖 this page came from ./arch/x86/include/asm, dated October 2026, and it's the x86_spec_ctrl_restore_host(9) manual page — periodt 🎀🦋