On 2/19/2025 6:14 PM, Francesco Lavra wrote:
On Fri, 2025-01-24 at 08:20 -0500, Xiaoyao Li wrote:
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 45867dbe0839..e35a9fbd687e 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -540,8 +540,15 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
+ /*
+ * tdx_pre_create_vcpu() may call cpu_x86_cpuid(). It in turn
may call
+ * kvm_vm_ioctl(). Set cpu->kvm_state in advance to avoid NULL
pointer
+ * dereference.
+ */
+ cpu->kvm_state = s;
This assignment should be removed from kvm_create_vcpu(), as now it's
redundant there.
I'll just drop the change in this patch since there is no dependency in
cpu_x86_cpuid() in current upstream QEMU.
ret = kvm_arch_pre_create_vcpu(cpu, errp);
if (ret < 0) {
+ cpu->kvm_state = NULL;
No need to reset cpu->kvm_state to NULL, there already are other error
conditions under which cpu->kvm_state remains initialized.
goto err;
}
@@ -550,6 +557,7 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
error_setg_errno(errp, -ret,
"kvm_init_vcpu: kvm_create_vcpu failed
(%lu)",
kvm_arch_vcpu_id(cpu));
+ cpu->kvm_state = NULL;
Same here.
