From: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
To enter a secure guest, we have to go through the ultravisor, therefore
we do a ucall when we are entering a secure guest.
This change is needed for any sort of entry to the secure guest from the
hypervisor, whether it is a return from an hcall, a return from a
hypervisor interrupt, or the first time that a secure guest vCPU is run.
If we are returning from an hcall, the results are already in the
appropriate registers (R3:12), except for R6,7, which need to be
restored before doing the ucall (UV_RETURN).
Have fast_guest_return check the kvm_arch.secure_guest field so that a
new CPU enters UV when started (in response to a RTAS start-cpu call).
Thanks to input from Paul Mackerras, Ram Pai and Mike Anderson.
Signed-off-by: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
[Pass SRR1 in r11 for UV_RETURN, fix kvmppc_msr_interrupt to preserve
the MSR_S bit]
Signed-off-by: Paul Mackerras <paulus@xxxxxxxxxx>
[Fix UV_RETURN token number and arch.secure_guest check]
Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
[Update commit message and ret_to_ultra comment]
Signed-off-by: Claudio Carvalho <cclaudio@xxxxxxxxxxxxx>
---
arch/powerpc/include/asm/kvm_host.h | 1 +
arch/powerpc/include/asm/ultravisor-api.h | 1 +
arch/powerpc/kernel/asm-offsets.c | 1 +
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 37 +++++++++++++++++++----
4 files changed, 34 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 013c76a0a03e..184becb62ea4 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -294,6 +294,7 @@ struct kvm_arch {
cpumask_t cpu_in_guest;
u8 radix;
u8 fwnmi_enabled;
+ u8 secure_guest;
bool threads_indep;
bool nested_enable;
pgd_t *pgtable;
diff --git a/arch/powerpc/include/asm/ultravisor-api.h b/arch/powerpc/include/asm/ultravisor-api.h
index 24bfb4c1737e..15e6ce77a131 100644
--- a/arch/powerpc/include/asm/ultravisor-api.h
+++ b/arch/powerpc/include/asm/ultravisor-api.h
@@ -19,5 +19,6 @@
/* opcodes */
#define UV_WRITE_PATE 0xF104
+#define UV_RETURN 0xF11C
#endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8e02444e9d3d..44742724513e 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -508,6 +508,7 @@ int main(void)
OFFSET(KVM_VRMA_SLB_V, kvm, arch.vrma_slb_v);
OFFSET(KVM_RADIX, kvm, arch.radix);
OFFSET(KVM_FWNMI, kvm, arch.fwnmi_enabled);
+ OFFSET(KVM_SECURE_GUEST, kvm, arch.secure_guest);
OFFSET(VCPU_DSISR, kvm_vcpu, arch.shregs.dsisr);
OFFSET(VCPU_DAR, kvm_vcpu, arch.shregs.dar);
OFFSET(VCPU_VPA, kvm_vcpu, arch.vpa.pinned_addr);
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index cffb365d9d02..d719d730d31e 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -36,6 +36,7 @@
#include <asm/asm-compat.h>
#include <asm/feature-fixups.h>
#include <asm/cpuidle.h>
+#include <asm/ultravisor-api.h>
/* Sign-extend HDEC if not on POWER9 */
#define EXTEND_HDEC(reg) \
@@ -1092,16 +1093,12 @@ BEGIN_FTR_SECTION
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
ld r5, VCPU_LR(r4)
- ld r6, VCPU_CR(r4)
mtlr r5
- mtcr r6
ld r1, VCPU_GPR(R1)(r4)
ld r2, VCPU_GPR(R2)(r4)
ld r3, VCPU_GPR(R3)(r4)
ld r5, VCPU_GPR(R5)(r4)
- ld r6, VCPU_GPR(R6)(r4)
- ld r7, VCPU_GPR(R7)(r4)
ld r8, VCPU_GPR(R8)(r4)
ld r9, VCPU_GPR(R9)(r4)
ld r10, VCPU_GPR(R10)(r4)
@@ -1119,10 +1116,35 @@ BEGIN_FTR_SECTION
mtspr SPRN_HDSISR, r0
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+ ld r6, VCPU_KVM(r4)
+ lbz r7, KVM_SECURE_GUEST(r6)
+ cmpdi r7, 0
+ bne ret_to_ultra
+
+ lwz r6, VCPU_CR(r4)
+ mtcr r6
+
+ ld r7, VCPU_GPR(R7)(r4)
+ ld r6, VCPU_GPR(R6)(r4)
ld r0, VCPU_GPR(R0)(r4)
ld r4, VCPU_GPR(R4)(r4)
HRFI_TO_GUEST
b .
+/*
+ * We are entering a secure guest, so we have to invoke the ultravisor to do
+ * that. If we are returning from a hcall, the results are already in the
+ * appropriate registers (R3:12), except for R6,7 which we used as temporary
+ * registers above. Restore them, and set R0 to the ucall number (UV_RETURN).
+ */
+ret_to_ultra:
+ lwz r6, VCPU_CR(r4)
+ mtcr r6
+ mfspr r11, SPRN_SRR1
+ LOAD_REG_IMMEDIATE(r0, UV_RETURN)
+ ld r7, VCPU_GPR(R7)(r4)
+ ld r6, VCPU_GPR(R6)(r4)
+ ld r4, VCPU_GPR(R4)(r4)
+ sc 2
/*
* Enter the guest on a P9 or later system where we have exactly
@@ -3318,13 +3340,16 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
* r0 is used as a scratch register
*/
kvmppc_msr_interrupt:
+ andis. r0, r11, MSR_S@h
rldicl r0, r11, 64 - MSR_TS_S_LG, 62
- cmpwi r0, 2 /* Check if we are in transactional state.. */
+ cmpwi cr1, r0, 2 /* Check if we are in transactional state.. */
ld r11, VCPU_INTR_MSR(r9)
- bne 1f
+ bne cr1, 1f
/* ... if transactional, change to suspended */
li r0, 1
1: rldimi r11, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+ beqlr
+ oris r11, r11, MSR_S@h /* preserve MSR_S bit setting */
blr
/*
--
2.20.1
