Re: [PATCH v4 00/21] Support SDEI Virtualization

[Gavin Shan <gshan@redhat.com>]

On 8/15/21 10:13 AM, Gavin Shan wrote:
> This series intends to virtualize Software Delegated Exception Interface
> (SDEI), which is defined by DEN0054A. It allows the hypervisor to deliver
> NMI-alike event to guest and it's needed by asynchronous page fault to
> deliver page-not-present notification from hypervisor to guest. The code
> and the required qemu changes can be found from:
> 
>     https://developer.arm.com/documentation/den0054/latest
>     https://github.com/gwshan/linux    ("kvm/arm64_sdei")
>     https://github.com/gwshan/qemu     ("kvm/arm64_sdei")
> 
> The SDEI event is identified by a 32-bits number. Bits[31:24] are used
> to indicate the SDEI event properties while bits[23:0] are identifying
> the unique number. The implementation takes bits[23:22] to indicate the
> owner of the SDEI event. For example, those SDEI events owned by KVM
> should have these two bits set to 0b01. Besides, the implementation
> supports SDEI events owned by KVM only.
> 
> The design is pretty straightforward and the implementation is just
> following the SDEI specification, to support the defined SMCCC intefaces,
> except the IRQ binding stuff. There are several data structures introduced.
> Some of the objects have to be migrated by VMM. So their definitions are
> split up for VMM to include the corresponding states for migration.
> 
>     struct kvm_sdei_kvm
>        Associated with VM and used to track the KVM exposed SDEI events
>        and those registered by guest.
>     struct kvm_sdei_vcpu
>        Associated with vCPU and used to track SDEI event delivery. The
>        preempted context is saved prior to the delivery and restored
>        after that.
>     struct kvm_sdei_event
>        SDEI events exposed by KVM so that guest can register and enable.
>     struct kvm_sdei_kvm_event
>        SDEI events that have been registered by guest.
>     struct kvm_sdei_vcpu_event
>        SDEI events that have been queued to specific vCPU for delivery.
> 
> The series is organized as below:
> 
>     PATCH[01]    Introduces template for smccc_get_argx()
>     PATCH[02]    Introduces the data structures and infrastructure
>     PATCH[03-14] Supports various SDEI related hypercalls
>     PATCH[15]    Supports SDEI event notification
>     PATCH[16-17] Introduces ioctl command for migration
>     PATCH[18-19] Supports SDEI event injection and cancellation
>     PATCH[20]    Exports SDEI capability
>     PATCH[21]    Adds self-test case for SDEI virtualization
> 

[...]

I explicitly copied James Morse and Mark Rutland when posting the series,
but something unknown went wrong. I'm including them here to avoid
reposting the whole series.

Thanks,
Gavin