[PATCH 5/6] KVM: PPC: Use CLASS(kvm_vcpu_map_local_readonly) for patching dcbz
From: Sean Christopherson <seanjc@google.com>
Date: 2026-07-24 00:48:08
Also in:
kvm, lkml
Subsystem:
kernel virtual machine for powerpc (kvm/powerpc), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Convert the kvm_vcpu_map() usage in PPC dcbz patching to the new CLASS(kvm_vcpu_map_local) implementation, to eliminate the very last of the the open-coded on-stack "struct kvm_host_map" declarations. This will allow adding hardening kvm_vcpu_map() against memory leaks (due to clobbering the existing mapping). No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/powerpc/kvm/book3s_pr.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 2ba2dd26a7ea..da7a038e2700 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c@@ -639,27 +639,24 @@ static void kvmppc_set_pvr_pr(struct kvm_vcpu *vcpu, u32 pvr) */ static void kvmppc_patch_dcbz(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte) { - struct kvm_host_map map; u64 hpage_offset; u32 *page; int i, r; - r = kvm_vcpu_map(vcpu, pte->raddr >> PAGE_SHIFT, &map); - if (r) + CLASS(kvm_vcpu_map_local, m)(vcpu, pte->raddr >> PAGE_SHIFT); + if (m.ret) return; hpage_offset = pte->raddr & ~PAGE_MASK; hpage_offset &= ~0xFFFULL; hpage_offset /= 4; - page = map.hva; + page = m.map.hva; /* patch dcbz into reserved instruction, so we trap */ for (i=hpage_offset; i < hpage_offset + (HW_PAGE_SIZE / 4); i++) if ((be32_to_cpu(page[i]) & 0xff0007ff) == INS_DCBZ) page[i] &= cpu_to_be32(0xfffffff7); - - kvm_vcpu_unmap(vcpu, &map); } static bool kvmppc_visible_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
--
2.55.0.229.g6434b31f56-goog