| Message ID | 20210722141340.2367905-1-farosas@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kvm: ppc: Print meaningful message on KVM_CREATE_VM failure | expand |
On Thu, Jul 22, 2021 at 11:13:40AM -0300, Fabiano Rosas wrote: > PowerPC has two KVM types (HV, PR) that translate into three kernel > modules: > > kvm.ko - common kvm code > kvm_hv.ko - kvm running with MSR_HV=1 or MSR_HV|PR=0 in a nested guest. > kvm_pr.ko - kvm running in usermode MSR_PR=1. > > Since the two KVM types can both be running at the same time, this > creates a situation in which it is possible for one or both of the > modules to fail to initialize, leaving the generic one behind. This > leads QEMU to think it can create a guest, but KVM will fail when > calling the type-specific code: > > ioctl(KVM_CREATE_VM) failed: 22 Invalid argument > qemu-kvm: failed to initialize KVM: Invalid argument > > Ideally this would be solved kernel-side, but it might be a while > until we can get rid of one of the modules. So in the meantime this > patch tries to make this less confusing for the end user by adding a > more elucidative message: > > ioctl(KVM_CREATE_VM) failed: 22 Invalid argument > PPC KVM module is not loaded. Try 'modprobe kvm_hv'. > > Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Applied to ppc-for-6.1, thanks. > --- > accel/kvm/kvm-all.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > index 3bd17135ce..4d9a7c7bfc 100644 > --- a/accel/kvm/kvm-all.c > +++ b/accel/kvm/kvm-all.c > @@ -2397,6 +2397,12 @@ static int kvm_init(MachineState *ms) > "- for kernels supporting the vm.allocate_pgste sysctl, " > "whether it is enabled\n"); > } > +#elif TARGET_PPC > + if (ret == -EINVAL) { > + fprintf(stderr, > + "PPC KVM module is not loaded. Try modprobe kvm_%s.\n", > + (type == 2) ? "pr" : "hv"); > + } > #endif > goto err; > }
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 3bd17135ce..4d9a7c7bfc 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -2397,6 +2397,12 @@ static int kvm_init(MachineState *ms) "- for kernels supporting the vm.allocate_pgste sysctl, " "whether it is enabled\n"); } +#elif TARGET_PPC + if (ret == -EINVAL) { + fprintf(stderr, + "PPC KVM module is not loaded. Try modprobe kvm_%s.\n", + (type == 2) ? "pr" : "hv"); + } #endif goto err; }
PowerPC has two KVM types (HV, PR) that translate into three kernel modules: kvm.ko - common kvm code kvm_hv.ko - kvm running with MSR_HV=1 or MSR_HV|PR=0 in a nested guest. kvm_pr.ko - kvm running in usermode MSR_PR=1. Since the two KVM types can both be running at the same time, this creates a situation in which it is possible for one or both of the modules to fail to initialize, leaving the generic one behind. This leads QEMU to think it can create a guest, but KVM will fail when calling the type-specific code: ioctl(KVM_CREATE_VM) failed: 22 Invalid argument qemu-kvm: failed to initialize KVM: Invalid argument Ideally this would be solved kernel-side, but it might be a while until we can get rid of one of the modules. So in the meantime this patch tries to make this less confusing for the end user by adding a more elucidative message: ioctl(KVM_CREATE_VM) failed: 22 Invalid argument PPC KVM module is not loaded. Try 'modprobe kvm_hv'. Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> --- accel/kvm/kvm-all.c | 6 ++++++ 1 file changed, 6 insertions(+)