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numa: Print warning if no node is assigned to a CPU
We need all possible CPUs (including hotplug ones) to be present in the SRAT when QEMU starts. QEMU already does that correctly today, the only problem is that when a CPU is omitted from the NUMA configuration, it is silently assigned to node 0. Check if all CPUs up to max_cpus are present in the NUMA configuration and warn about missing CPUs. Make it just a warning, to allow management software to be updated if necessary. In the future we may make it a fatal error instead. Command-line examples: * Correct, no warning: $ qemu-system-x86_64 -smp 2,maxcpus=4 $ qemu-system-x86_64 -smp 2,maxcpus=4 -numa node,cpus=0-3 * Incomplete, with warnings: $ qemu-system-x86_64 -smp 2,maxcpus=4 -numa node,cpus=0 qemu-system-x86_64: warning: CPU(s) not present in any NUMA nodes: 1 2 3 qemu-system-x86_64: warning: All CPU(s) up to maxcpus should be described in NUMA config $ qemu-system-x86_64 -smp 2,maxcpus=4 -numa node,cpus=0-2 qemu-system-x86_64: warning: CPU(s) not present in any NUMA nodes: 3 qemu-system-x86_64: warning: All CPU(s) up to maxcpus should be described in NUMA config Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> --- v1 -> v2: (no changes) v2 -> v3: * Use enumerate_cpus() and error_report() for error message * Simplify logic using bitmap_full() v3 -> v4: * Clarify error message, mention that all CPUs up to maxcpus need to be described in NUMA config v4 -> v5: * Commit log update, to make problem description clearer
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