[PATCH v5 2/5] LoongArch: KVM: Return directly when IPI address is not aligned

[Bibo Mao]

When IPI address is not aligned with its access size, it should return
directly in read/write operations, rather than only print WARN_ON_ONCE().
The method is the same with in kernel extioi and pch_pic operations.

Signed-off-by: Bibo Mao <maobibo@xxxxxxxxxxx>
---
 arch/loongarch/kvm/intc/ipi.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/loongarch/kvm/intc/ipi.c b/arch/loongarch/kvm/intc/ipi.c
index 4fa0897d7bdb..928f9bd5e1f1 100644
--- a/arch/loongarch/kvm/intc/ipi.c
+++ b/arch/loongarch/kvm/intc/ipi.c
@@ -186,9 +186,13 @@ static int loongarch_ipi_readl(struct kvm_vcpu *vcpu, gpa_t addr, int len, void
 	uint32_t offset;
 	uint64_t res = 0;
 
-	offset = (uint32_t)(addr & 0x1ff);
-	WARN_ON_ONCE(offset & (len - 1));
+	if (addr & (len - 1)) {
+		*(uint64_t *)val = res;
+		kvm_pr_unimpl("%s: ipi not aligned addr %llx len %d\n", __func__, addr, len);
+		return 0;
+	}
 
+	offset = addr - IOCSR_IPI_BASE;
 	switch (offset) {
 	case IOCSR_IPI_STATUS:
 		spin_lock(&vcpu->arch.ipi_state.lock);
@@ -204,11 +208,6 @@ static int loongarch_ipi_readl(struct kvm_vcpu *vcpu, gpa_t addr, int len, void
 	case IOCSR_IPI_CLEAR:
 		break;
 	case IOCSR_IPI_BUF_20 ... IOCSR_IPI_BUF_38 + 7:
-		if (offset + len > IOCSR_IPI_BUF_38 + 8) {
-			kvm_err("%s: invalid offset or len: offset = %d, len = %d\n",
-				__func__, offset, len);
-			break;
-		}
 		res = read_mailbox(vcpu, offset, len);
 		break;
 	default:
@@ -227,9 +226,12 @@ static int loongarch_ipi_writel(struct kvm_vcpu *vcpu, gpa_t addr, int len, cons
 
 	data = *(uint64_t *)val;
 
-	offset = (uint32_t)(addr & 0x1ff);
-	WARN_ON_ONCE(offset & (len - 1));
+	if (addr & (len - 1)) {
+		kvm_pr_unimpl("%s: ipi not aligned addr %llx len %d\n", __func__, addr, len);
+		return 0;
+	}
 
+	offset = addr - IOCSR_IPI_BASE;
 	switch (offset) {
 	case IOCSR_IPI_STATUS:
 		break;
-- 
2.39.3