KVM: PPC: Book3S PR: Preserve storage control bits
PR KVM page fault handler performs eaddr to pte translation for a guest,
however kvmppc_mmu_book3s_64_xlate() does not preserve WIMG bits
(storage control) in the kvmppc_pte struct. If PR KVM is running as
a second level guest under HV KVM, and PR KVM tries inserting HPT entry,
this fails in HV KVM if it already has this mapping.
This preserves WIMG bits between kvmppc_mmu_book3s_64_xlate() and
kvmppc_mmu_map_page().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 2acc691..0f3ac09 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -342,6 +342,7 @@ struct kvmppc_pte {
bool may_read : 1;
bool may_write : 1;
bool may_execute : 1;
+ unsigned long wimg;
u8 page_size; /* MMU_PAGE_xxx */
};
diff --git a/arch/powerpc/kvm/book3s_64_mmu.c b/arch/powerpc/kvm/book3s_64_mmu.c
index 7015357..29ebe2f 100644
--- a/arch/powerpc/kvm/book3s_64_mmu.c
+++ b/arch/powerpc/kvm/book3s_64_mmu.c
@@ -319,6 +319,7 @@ static int kvmppc_mmu_book3s_64_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
gpte->may_execute = true;
gpte->may_read = false;
gpte->may_write = false;
+ gpte->wimg = r & HPTE_R_WIMG;
switch (pp) {
case 0:
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
index 4b4e927..145a618 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -145,6 +145,8 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
else
kvmppc_mmu_flush_icache(pfn);
+ rflags = (rflags & ~HPTE_R_WIMG) | orig_pte->wimg;
+
/*
* Use 64K pages if possible; otherwise, on 64K page kernels,
* we need to transfer 4 more bits from guest real to host real addr.
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index ce437b9..f026b06 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -537,7 +537,7 @@ int kvmppc_handle_pagefault(struct kvm_run *run, struct kvm_vcpu *vcpu,
int r = RESUME_GUEST;
int relocated;
int page_found = 0;
- struct kvmppc_pte pte;
+ struct kvmppc_pte pte = { 0 };
bool dr = (kvmppc_get_msr(vcpu) & MSR_DR) ? true : false;
bool ir = (kvmppc_get_msr(vcpu) & MSR_IR) ? true : false;
u64 vsid;