kvm_trap_vz...cop_unusable(9)

💅 kvm_trap_vz...cop_unusable — the Kernel API Manual, bestie edition 🎀

okay so real talk, this is a page from the Kernel API Manual and it's all about kvm_trap_vz_handle_cop_unusable. yes the title has dots in it, no that's not a typo, that's just how the page is named. we move 💅

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✨ NAME ✨

kvm_trap_vz_handle_cop_unusable — literally the guest tried to use a coprocessor and got told no 🚫

✨ SYNOPSIS ✨

int kvm_trap_vz_handle_cop_unusable (struct kvm_vcpu *vcpu );

✨ ARGUMENTS ✨

• vcpu — the Virtual CPU context, aka the main character of this whole situation 👑

✨ DESCRIPTION ✨

so here's the vibe: this function handles the moment when the guest goes and tries to use a coprocessor that hasn't been allowed by the root context. like, guest bestie… you don't have permission for that 💀

that's it, that's the whole job. it catches the audacity and deals with it.

✨ RETURN ✨

returns a value indicating whether to resume the host or the guest — specifically one of RESUME_HOST or RESUME_GUEST 🦋

✨ SEE ALSO ✨

• the Kernel file ./arch/mips/kvm/vz.c (that's the home base, go look 🏠)
• kvm_vz_should_use_htimer(9)
• _kvm_vz_restore_stimer(9)
• _kvm_vz_restore_htimer(9)
• kvm_vz_restore_timer(9)
• kvm_vz_acquire_htimer(9)
• _kvm_vz_save_htimer(9)
• kvm_vz_save_timer(9)
• kvm_vz_lose_htimer(9)
• is_eva_access(9)
• is_eva_am_mapped(9)
• kvm_vz_gva_to_gpa(9)
• kvm_vz_badvaddr_to_gpa(9)
• kvm_trap_vz_handle_msa_disabled(9)
• kvm_vz_resize_guest_vtlb(9)

like, that's a whole friend group of timer and address functions, and honestly? we stan a supportive ecosystem 🌈

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and that's the page!! 🫶 this one came out in ./arch/mips/kvm and it's dated October 2026, and it's literally titled kvm_trap_vz...cop_unusable(9) in case you need to cite it in your group chat. mwah, study hard, drink water, and don't use coprocessors you don't have permission for 😭✨💖