KVM: PPC: Book3S HV: Nested guest entry via hypercall
This adds a new hypercall, H_ENTER_NESTED, which is used by a nested
hypervisor to enter one of its nested guests. The hypercall supplies
register values in two structs. Those values are copied by the level 0
(L0) hypervisor (the one which is running in hypervisor mode) into the
vcpu struct of the L1 guest, and then the guest is run until an
interrupt or error occurs which needs to be reported to L1 via the
hypercall return value.
Currently this assumes that the L0 and L1 hypervisors are the same
endianness, and the structs passed as arguments are in native
endianness. If they are of different endianness, the version number
check will fail and the hcall will be rejected.
Nested hypervisors do not support indep_threads_mode=N, so this adds
code to print a warning message if the administrator has set
indep_threads_mode=N, and treat it as Y.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 9cea2386..a945369 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1393,6 +1393,10 @@
BEGIN_FTR_SECTION
PPC_MSGSYNC
lwsync
+ /* always exit if we're running a nested guest */
+ ld r0, VCPU_NESTED(r9)
+ cmpdi r0, 0
+ bne guest_exit_cont
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
lbz r0, HSTATE_HOST_IPI(r13)
cmpwi r0, 0
@@ -2199,6 +2203,10 @@
andi. r0,r11,MSR_PR
/* sc 1 from userspace - reflect to guest syscall */
bne sc_1_fast_return
+ /* sc 1 from nested guest - give it to L1 to handle */
+ ld r0, VCPU_NESTED(r9)
+ cmpdi r0, 0
+ bne guest_exit_cont
clrrdi r3,r3,2
cmpldi r3,hcall_real_table_end - hcall_real_table
bge guest_exit_cont