[PATCH kvmtool 1/2] arm64: Honor --vcpu-affinity for aarch32 guests

[Alexandru Elisei]

Commit 4639b72f61a3 ("arm64: Add --vcpu-affinity command line argument")
introduced the --vcpu-affinity command line argument to pin the VCPUs to a
given list of physical CPUs. Unfortunately, the affinity is set only for an
arm64 guest, leading to the following error when running a 32-bit guest on
a system with two or more PMUs:

KVM exit reason: 9 ("KVM_EXIT_FAIL_ENTRY")

 Registers:
 PC:    0x8000c608
 PSTATE:    0x200000d3
 SP_EL1:    0x0
 LR:    0x0

*pc:
 0x8000c608: 25 3f a0 e1  83 61 a0 e1
 0x8000c610: 83 31 98 e7  04 10 82 e1
 0x8000c618: 07 2c 81 e3  28 10 1b e5
 0x8000c620: 03 20 82 e3  03 00 a0 e1

*lr:
  Warning: unable to translate guest address 0x0 to host
 0x00000000: <unknown>
 0x00000008: <unknown>
 0x00000010: <unknown>
 0x00000018: <unknown>

  # KVM compatibility warning.
	virtio-net device was not detected.
	While you have requested a virtio-net device, the guest kernel did not initialize it.
	Please make sure that the guest kernel was compiled with CONFIG_VIRTIO_NET=y enabled in .config.

  # KVM session ended normally.

Make the error go away by setting the affinity of the VCPUs for both 32-bit
and 64-bit guests.

Fixes: 4639b72f61a3 ("arm64: Add --vcpu-affinity command line argument")
Signed-off-by: Alexandru Elisei <alexandru.elisei at arm.com>
---
 arm/aarch64/kvm-cpu.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/arm/aarch64/kvm-cpu.c b/arm/aarch64/kvm-cpu.c
index 4ac0fafae06b..c8be10b3ca94 100644
--- a/arm/aarch64/kvm-cpu.c
+++ b/arm/aarch64/kvm-cpu.c
@@ -88,16 +88,7 @@ static void reset_vcpu_aarch64(struct kvm_cpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
 	struct kvm_one_reg reg;
-	cpu_set_t *affinity;
 	u64 data;
-	int ret;
-
-	affinity = kvm->arch.vcpu_affinity_cpuset;
-	if (affinity) {
-		ret = sched_setaffinity(0, sizeof(cpu_set_t), affinity);
-		if (ret == -1)
-			die_perror("sched_setaffinity");
-	}
 
 	reg.addr = (u64)&data;
 
@@ -179,7 +170,18 @@ int kvm_cpu__configure_features(struct kvm_cpu *vcpu)
 
 void kvm_cpu__reset_vcpu(struct kvm_cpu *vcpu)
 {
-	if (vcpu->kvm->cfg.arch.aarch32_guest)
+	struct kvm *kvm = vcpu->kvm;
+	cpu_set_t *affinity;
+	int ret;
+
+	affinity = kvm->arch.vcpu_affinity_cpuset;
+	if (affinity) {
+		ret = sched_setaffinity(0, sizeof(cpu_set_t), affinity);
+		if (ret == -1)
+			die_perror("sched_setaffinity");
+	}
+
+	if (kvm->cfg.arch.aarch32_guest)
 		return reset_vcpu_aarch32(vcpu);
 	else
 		return reset_vcpu_aarch64(vcpu);
-- 
2.36.1