On 25/07/2023 14.26, Andrew Jones wrote:
Since Linux commit 00f918f61c56 ("RISC-V: KVM: Skeletal in-kernel AIA irqchip support") checking KVM_CAP_IRQCHIP returns non-zero when the RISC-V platform has AIA. The cap indicates KVM supports at least one of the following ioctls:KVM_CREATE_IRQCHIP KVM_IRQ_LINE KVM_GET_IRQCHIP KVM_SET_IRQCHIP KVM_GET_LAPIC KVM_SET_LAPIC but the cap doesn't imply that KVM must support any of those ioctls in particular. However, QEMU was assuming the KVM_CREATE_IRQCHIP ioctl was supported. Stop making that assumption by introducing a KVM parameter that each architecture which supports KVM_CREATE_IRQCHIP sets. Adding parameters isn't awesome, but given how the KVM_CAP_IRQCHIP isn't very helpful on its own, we don't have a lot of options. Signed-off-by: Andrew Jones <ajo...@ventanamicro.com> --- While this fixes booting guests on riscv KVM with AIA it's unlikely to get merged before the QEMU support for KVM AIA[1] lands, which would also fix the issue. I think this patch is still worth considering though since QEMU's assumption is wrong. [1] https://lore.kernel.org/all/20230714084429.22349-1-yongxuan.w...@sifive.com/ v2: - Move the s390x code to an s390x file. [Thomas] - Drop the KVM_CAP_IRQCHIP check from the top of kvm_irqchip_create(), as it's no longer necessary.
Looks good now! Reviewed-by: Thomas Huth <th...@redhat.com>
