Re: [libvirt] [PATCH v7 2/4] arm: enhance kvm_arm_create_scratch_host_vcpu

Some more lines to make sure we allow NULL for 1st/3rd parameter. Signed-off-by: Peter Xu <peterx(a)redhat.com&gt;

--- target-arm/kvm.c | 14 +++++++++++++- target-arm/kvm_arm.h | 6 ++++-- 2 files changed, 17 insertions(+), 3 deletions(-) diff --git a/target-arm/kvm.c b/target-arm/kvm.c index 969ab0b..bb6935e 100644 --- a/target-arm/kvm.c +++ b/target-arm/kvm.c @@ -62,13 +62,17 @@ bool kvm_arm_create_scratch_host_vcpu(const uint32_t *cpus_to_try, goto err; } + if (!init) { + goto finish; + } + ret = ioctl(vmfd, KVM_ARM_PREFERRED_TARGET, init); if (ret >= 0) { ret = ioctl(cpufd, KVM_ARM_VCPU_INIT, init); if (ret < 0) { goto err; } - } else { + } else if (cpus_to_try) { /* Old kernel which doesn't know about the * PREFERRED_TARGET ioctl: we know it will only support * creating one kind of guest CPU which is its preferred @@ -85,8 +89,16 @@ bool kvm_arm_create_scratch_host_vcpu(const uint32_t *cpus_to_try, if (ret < 0) { goto err; } + } else { + /* + * Here, we got init != NULL but cpus_to_retry == NULL, + * meanwhile, we failed to probe one preferred target type + * (no matter what). So we fail. + */ + goto err; } +finish: fdarray[0] = kvmfd; fdarray[1] = vmfd; fdarray[2] = cpufd; diff --git a/target-arm/kvm_arm.h b/target-arm/kvm_arm.h index 07f0c72..4f01a99 100644 --- a/target-arm/kvm_arm.h +++ b/target-arm/kvm_arm.h @@ -124,9 +124,11 @@ void kvm_arm_reset_vcpu(ARMCPU *cpu); * kvm_arm_create_scratch_host_vcpu: * @cpus_to_try: array of QEMU_KVM_ARM_TARGET_* values (terminated with * QEMU_KVM_ARM_TARGET_NONE) to try as fallback if the kernel does not - * know the PREFERRED_TARGET ioctl + * know the PREFERRED_TARGET ioctl. If NULL is provided, will try + * to use perferred target, and fail if no preferred found. * @fdarray: filled in with kvmfd, vmfd, cpufd file descriptors in that order - * @init: filled in with the necessary values for creating a host vcpu + * @init: filled in with the necessary values for creating a host + * vcpu. If NULL is provided, will not init the vCPU. * * Create a scratch vcpu in its own VM of the type preferred by the host * kernel (as would be used for '-cpu host'), for purposes of probing it