Messages in this thread | | | Subject | Re: [RFC PATCH 00/32] ACPI/arm64: add support for virtual cpuhotplug | From | Gavin Shan <> | Date | Mon, 3 Apr 2023 14:25:36 +0800 |
| |
Hi Shaoqin,
On 3/29/23 1:52 PM, Shaoqin Huang wrote: > On 2/3/23 21:50, James Morse wrote:
[...]
>> >> The first patch has already been posted as a fix here: >> https://www.spinics.net/lists/linux-ia64/msg21920.html >> I've only build tested Loongarch and ia64. >> >> >> If folk want to play along at home, you'll need a copy of Qemu that supports this. >> https://github.com/salil-mehta/qemu.git salil/virt-cpuhp-armv8/rfc-v1-port29092022.psci.present >> >> You'll need to fix the numbers of KVM_CAP_ARM_HVC_TO_USER and KVM_CAP_ARM_PSCI_TO_USER >> to match your host kernel. Replace your '-smp' argument with something like: >> | -smp cpus=1,maxcpus=3,cores=3,threads=1,sockets=1 >> >> then feed the following to the Qemu montior; >> | (qemu) device_add driver=host-arm-cpu,core-id=1,id=cpu1 >> | (qemu) device_del cpu1 >> >> >> This series is based on v6.2-rc3, and can be retrieved from: >> https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git/ virtual_cpu_hotplug/rfc/v1 > > I applied this patch series on v6.2-rc3 and using the QEMU cloned from the salil-mehta/qemu.git repo. But when I try to run the QEMU, it shows: > > $ qemu-system-aarch64: -accel kvm: Failed to enable KVM_CAP_ARM_PSCI_TO_USER cap. > > Here is the command I use: > > $ qemu-system-aarch64 > -machine virt > -bios /usr/share/qemu-efi-aarch64/QEMU_EFI.fd > -accel kvm > -m 4096 > -smp cpus=1,maxcpus=3,cores=3,threads=1,sockets=1 > -cpu host > -qmp unix:./src.socket,server,nowait > -hda ./XXX.qcow2 > -serial unix:./src.serial,server,nowait > -monitor stdio > > It seems something related to your notice: You'll need to fix the numbers of KVM_CAP_ARM_HVC_TO_USER and KVM_CAP_ARM_PSCI_TO_USER > to match your host kernel. > > But I'm not actually understand what should I fix, since I haven't review the patch series. Could you give me some more information? Maybe I'm doing something wrong. >
When the kernel is rebased to v6.2.rc3, the two capabilities are conflictsing between QEMU and host kernel. Please adjust them like below and have a try:
In qemu/linux-headers/linux/kvm.h
#define KVM_CAP_ARM_HVC_TO_USER 250 /* TODO: as per linux 6.1-rc2 */ #define KVM_CAP_ARM_PSCI_TO_USER 251 /* TODO: as per linux 6.1-rc2 */
In linux/include/uapi/linux/kvm.h
#define KVM_CAP_ARM_HVC_TO_USER 250 #define KVM_CAP_ARM_PSCI_TO_USER 251
Thanks, Gavin
| |