[PATCH 3/4] KVM: RISC-V: replace system_event.flags with ndata and data[0]

[Paolo Bonzini <pbonzini@redhat.com>]

The flags datum for KVM_EXIT_SYSTEM_EVENT exits has been
removed because it was defined incorrectly; no padding was
introduced between the 32-bit type and the 64-bit flags,
resulting in different definitions for 32-bit and 64-bit
userspace.

The replacement is a pair of fields, ndata and data[],
with ndata saying how many items are valid in the data array.
In the case of RISC-V that's one for the SRST SBI call (with
flags simply moved to data[0]) and zero for the legacy v0.1
call.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/riscv/include/asm/kvm_vcpu_sbi.h | 2 +-
 arch/riscv/kvm/vcpu_sbi.c             | 5 +++--
 arch/riscv/kvm/vcpu_sbi_replace.c     | 4 ++--
 arch/riscv/kvm/vcpu_sbi_v01.c         | 2 +-
 4 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h
index 83d6d4d2b1df..c4b10c25264a 100644
--- a/arch/riscv/include/asm/kvm_vcpu_sbi.h
+++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h
@@ -30,7 +30,7 @@ struct kvm_vcpu_sbi_extension {
 void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run);
 void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu,
 				     struct kvm_run *run,
-				     u32 type, u64 flags);
+				     u32 type, bool have_reason, u64 reason);
 const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid);
 
 #endif /* __RISCV_KVM_VCPU_SBI_H__ */
diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
index a09ecb97b890..2019ca01b44b 100644
--- a/arch/riscv/kvm/vcpu_sbi.c
+++ b/arch/riscv/kvm/vcpu_sbi.c
@@ -83,7 +83,7 @@ void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run)
 
 void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu,
 				     struct kvm_run *run,
-				     u32 type, u64 flags)
+				     u32 type, bool have_reason, u64 reason)
 {
 	unsigned long i;
 	struct kvm_vcpu *tmp;
@@ -94,7 +94,8 @@ void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu,
 
 	memset(&run->system_event, 0, sizeof(run->system_event));
 	run->system_event.type = type;
-	run->system_event.flags = flags;
+	run->system_event.ndata = have_reason;
+	run->system_event.data[0] = reason;
 	run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
 }
 
diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c
index 0f217365c287..a36414a5f59e 100644
--- a/arch/riscv/kvm/vcpu_sbi_replace.c
+++ b/arch/riscv/kvm/vcpu_sbi_replace.c
@@ -148,14 +148,14 @@ static int kvm_sbi_ext_srst_handler(struct kvm_vcpu *vcpu,
 		case SBI_SRST_RESET_TYPE_SHUTDOWN:
 			kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
 						KVM_SYSTEM_EVENT_SHUTDOWN,
-						reason);
+						true, reason);
 			*exit = true;
 			break;
 		case SBI_SRST_RESET_TYPE_COLD_REBOOT:
 		case SBI_SRST_RESET_TYPE_WARM_REBOOT:
 			kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
 						KVM_SYSTEM_EVENT_RESET,
-						reason);
+						true, reason);
 			*exit = true;
 			break;
 		default:
diff --git a/arch/riscv/kvm/vcpu_sbi_v01.c b/arch/riscv/kvm/vcpu_sbi_v01.c
index da4d6c99c2cf..9598bc6b4c0e 100644
--- a/arch/riscv/kvm/vcpu_sbi_v01.c
+++ b/arch/riscv/kvm/vcpu_sbi_v01.c
@@ -66,7 +66,7 @@ static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
 		break;
 	case SBI_EXT_0_1_SHUTDOWN:
 		kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
-						KVM_SYSTEM_EVENT_SHUTDOWN, 0);
+						KVM_SYSTEM_EVENT_SHUTDOWN, false, 0);
 		*exit = true;
 		break;
 	case SBI_EXT_0_1_REMOTE_FENCE_I:
-- 
2.31.1