mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-07 13:57:54 -04:00
Code Issues Packages Projects Releases Wiki Activity

KVM: x86/mmu: Detect if unprotect will do anything based on invalid_list

Browse Source 
Explicitly query the list of to-be-zapped shadow pages when checking to
see if unprotecting a gfn for retry has succeeded, i.e. if KVM should
retry the faulting instruction.

Add a comment to explain why the list needs to be checked before zapping,
which is the primary motivation for this change.

No functional change intended.

Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Link: https://lore.kernel.org/r/20240831001538.336683-22-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Sean Christopherson
2024-08-30 17:15:36 -07:00
parent 6b3dcabc10
commit d859b16161
1 changed files with 7 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
arch/x86/kvm/mmu/mmu.c
View File

@@ -2721,12 +2721,15 @@ bool __kvm_mmu_unprotect_gfn_and_retry(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
goto out;
}
r = false;
write_lock(&kvm->mmu_lock);
for_each_gfn_valid_sp_with_gptes(kvm, sp, gpa_to_gfn(gpa)) {
r = true;
for_each_gfn_valid_sp_with_gptes(kvm, sp, gpa_to_gfn(gpa))
kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list);
}
/*
* Snapshot the result before zapping, as zapping will remove all list
* entries, i.e. checking the list later would yield a false negative.
*/
r = !list_empty(&invalid_list);
kvm_mmu_commit_zap_page(kvm, &invalid_list);
write_unlock(&kvm->mmu_lock);