diff options
| author | Greg Kurz <gkurz@linux.vnet.ibm.com> | 2016-04-26 15:41:04 +0200 |
|---|---|---|
| committer | David Gibson <david@gibson.dropbear.id.au> | 2016-05-27 09:40:23 +1000 |
| commit | 41264b385c2b324fea026204e5de9bef980733b1 (patch) | |
| tree | 2284acef24028c8f0ab0a642dc9516dcc62a8ae7 /target-ppc | |
| parent | 8afc22a20fba6aa078e4e7a625d16d78da768323 (diff) | |
PPC/KVM: early validation of vcpu id
The KVM API restricts vcpu ids to be < KVM_CAP_MAX_VCPUS. On PowerPC
targets, depending on the number of threads per core in the host and
in the guest, some topologies do generate higher vcpu ids actually.
When this happens, QEMU bails out with the following error:
kvm_init_vcpu failed: Invalid argument
The KVM_CREATE_VCPU ioctl has several EINVAL return paths, so it is
not possible to fully disambiguate.
This patch adds a check in the code that computes vcpu ids, so that
we can detect the error earlier, and print a friendlier message instead
of calling KVM_CREATE_VCPU with an obviously bogus vcpu id.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Diffstat (limited to 'target-ppc')
| -rw-r--r-- | target-ppc/translate_init.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c index 954195f5e4..a003c1029d 100644 --- a/target-ppc/translate_init.c +++ b/target-ppc/translate_init.c @@ -9231,6 +9231,14 @@ static void ppc_cpu_realizefn(DeviceState *dev, Error **errp) #if !defined(CONFIG_USER_ONLY) cpu->cpu_dt_id = (cs->cpu_index / smp_threads) * max_smt + (cs->cpu_index % smp_threads); + + if (kvm_enabled() && !kvm_vcpu_id_is_valid(cpu->cpu_dt_id)) { + error_setg(errp, "Can't create CPU with id %d in KVM", cpu->cpu_dt_id); + error_append_hint(errp, "Adjust the number of cpus to %d " + "or try to raise the number of threads per core\n", + cpu->cpu_dt_id * smp_threads / max_smt); + return; + } #endif if (tcg_enabled()) { |