kvm_gpc_check(9)

kvm_gpc_check(9) ✨

okay so welcome to the Kernel API Manual, bestie 💖 this page is all about kvm_gpc_check(9) and whether your gfn_to_pfn_cache is still valid. group-chat summary: it checks the cache, no cap.

🎀 NAME 🎀

kvm_gpc_check — check validity of a gfn_to_pfn_cache. 💅

🌸 SYNOPSIS 🌸

bool kvm_gpc_check (struct gfn_to_pfn_cache *gpc , unsigned long len );

🦋 ARGUMENTS 🦋

• gpc — a struct gfn_to_pfn_cache object. that's the cache babe, the main character here 👑
• len — sanity check; the range being access must fit a single page. so like keep it inside one page, periodt 📏

💖 RETURN 💖

• true — the cache is still valid and the address matches. slay ✨
• false — the cache is not valid. 💀

🔥 DESCRIPTION 🔥

okay so here's the lock lore, bestie 🔒. callers outside IN_GUEST_MODE context should hold a read lock on gpc->lock while calling this function, and then keep holding that lock until the access is complete. do not let go early, fr fr 🫶

callers in IN_GUEST_MODE may do so without locking, although they should still hold a read lock on kvm->scru for the memslot checks. that's the vibe check: no locking in that mode, but the kvm->scru read lock still matters for memslot checks. iykyk 👑

🌈 SEE ALSO 🌈

Kernel file: ./include/linux/kvm_host.h 🌸

also go peek at these icons:

• guest_state_enter_irqoff(9)
• guest_state_exit_irqoff(9)
• kvm_gpc_init(9)
• kvm_gpc_activate(9)
• kvm_gpc_activate_hva(9)
• kvm_gpc_refresh(9)
• kvm_gpc_deactivate(9)
• kvm_stats_linear_hist_update(9)
• kvm_stats_log_hist_update(9)

---

mwah 💋 — source/version is ./include/linux, dated October 2026, and this page is kvm_gpc_check(9) signing off. bye bestie, go check that cache! 🦋