KVM: PPC: Book3S: correct width in XER handling

In 64 bit kernels, the Fixed Point Exception Register (XER) is a 64
bit field (e.g. in kvm_regs and kvm_vcpu_arch) and in most places it is
accessed as such.

This patch corrects places where it is accessed as a 32 bit field by a
64 bit kernel.  In some cases this is via a 32 bit load or store
instruction which, depending on endianness, will cause either the
lower or upper 32 bits to be missed.  In another case it is cast as a
u32, causing the upper 32 bits to be cleared.

This patch corrects those places by extending the access methods to
64 bits.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

arch/powerpc/include/asm/kvm_book3s.h

@@ -226,12 +226,12 @@ static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
 	return vcpu->arch.cr;
 }
 
-static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, u32 val)
+static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
 {
 	vcpu->arch.xer = val;
 }
 
-static inline u32 kvmppc_get_xer(struct kvm_vcpu *vcpu)
+static inline ulong kvmppc_get_xer(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.xer;
 }

arch/powerpc/include/asm/kvm_book3s_asm.h

@@ -132,7 +132,7 @@ struct kvmppc_book3s_shadow_vcpu {
 	bool in_use;
 	ulong gpr[14];
 	u32 cr;
-	u32 xer;
+	ulong xer;
 	ulong ctr;
 	ulong lr;
 	ulong pc;

arch/powerpc/include/asm/kvm_booke.h

@@ -54,12 +54,12 @@ static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
 	return vcpu->arch.cr;
 }
 
-static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, u32 val)
+static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
 {
 	vcpu->arch.xer = val;
 }
 
-static inline u32 kvmppc_get_xer(struct kvm_vcpu *vcpu)
+static inline ulong kvmppc_get_xer(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.xer;
 }

arch/powerpc/kvm/book3s_hv_rmhandlers.S

@@ -944,7 +944,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	blt	hdec_soon
 
 	ld	r6, VCPU_CTR(r4)
-	lwz	r7, VCPU_XER(r4)
+	ld	r7, VCPU_XER(r4)
 
 	mtctr	r6
 	mtxer	r7
@@ -1181,7 +1181,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	mfctr	r3
 	mfxer	r4
 	std	r3, VCPU_CTR(r9)
-	stw	r4, VCPU_XER(r9)
+	std	r4, VCPU_XER(r9)
 
 	/* If this is a page table miss then see if it's theirs or ours */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DATA_STORAGE
@@ -1763,7 +1763,7 @@ kvmppc_hdsi:
 	bl	kvmppc_msr_interrupt
 fast_interrupt_c_return:
 6:	ld	r7, VCPU_CTR(r9)
-	lwz	r8, VCPU_XER(r9)
+	ld	r8, VCPU_XER(r9)
 	mtctr	r7
 	mtxer	r8
 	mr	r4, r9

arch/powerpc/kvm/book3s_segment.S

@@ -123,7 +123,7 @@ no_dcbz32_on:
 	PPC_LL	r8, SVCPU_CTR(r3)
 	PPC_LL	r9, SVCPU_LR(r3)
 	lwz	r10, SVCPU_CR(r3)
-	lwz	r11, SVCPU_XER(r3)
+	PPC_LL	r11, SVCPU_XER(r3)
 
 	mtctr	r8
 	mtlr	r9
@@ -237,7 +237,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 	mfctr	r8
 	mflr	r9
 
-	stw	r5, SVCPU_XER(r13)
+	PPC_STL	r5, SVCPU_XER(r13)
 	PPC_STL	r6, SVCPU_FAULT_DAR(r13)
 	stw	r7, SVCPU_FAULT_DSISR(r13)
 	PPC_STL	r8, SVCPU_CTR(r13)