Re: [Qemu-arm] [Qemu-devel] [PATCH 00/23] GICv3 emulation

[Shannon Zhao]

On 2016年05月10日 01:29, Peter Maydell wrote:
> This series implements emulation of the GICv3 interrupt controller.
> It is based to some extent on previous patches from Shlomo and
> Pavel, but the bulk of it has turned out to be new code. (The
> combination of changing the underlying data structures, adding
> support for TrustZone and implementing proper GICv3 behaviour rather
> than borrowing fragments of GICv2 emulation code meant there wasn't
> much left to reuse.) I've tried to reflect this in the various
> authorship credits on the patches, but please let me know if you
> feel I got anything miscredited one way or the other.
> 
> Key points about the GICv3 emulated here:
>  * "non-legacy" only, ie system registers and affinity routing
>  * TrustZone is implemented
>  * no virtualization support
>  * only the "core" GICv3, so no LPI support (via ITS or otherwise)
> 
> I have included the "support KVM save/restore" patches from Pavel,
> reworked to use the new data structures, but they are only RFC
> status because the kernel API is not yet final (there are a couple
> of loose threads there to be followed up). Those patches are at the
> end of the series; I think everything else is in a commitable state
> (give or take code review).
> 
> Testing: I have confirmed that we can boot a Linux guest kernel,
> but not tried any other GIC-using guest code. I've done some light
> stress-testing using 'stress', and checked an SMP (2-cpu) boot.
> 
> Design: all the code here is in hw/intc/, split into several
> files to avoid them being huge. The interface between the CPU
> proper and the CPU interface is a bit ad-hoc (you can see the
> awkward seams that result from the choice to think of the cpu
> i/f as part of the GIC device rather than part of the CPU itself),
> but I think that if you put the cpu i/f in the CPU you'd end up
> with an ad-hoc interface and awkward seams in the other direction.
> The GICv3 device currently assumes it is always connected to all
> CPUs; we can change that later to allow some kind of QOM link
> property to specify the CPUs explicitly, but I think this is OK
> for now (and it's already a pretty huge set of code changes to
> have to review).
> 
> I include a workaround for a Linux kernel bug which otherwise
> prevents booting on the virt board. I've reported the bug to
> Marc Zyngier and he should post a kernel patch to fix it shortly,
> but I think we'll need to retain the workaround for the benefit
> of older kernels (an ugly but pragmatic choice).
> 
> 
> Code review, testing, attempts to run guests other than Linux
> welcome (UEFI, anybody?)
> 
> thanks
> -- PMM
> 
> Pavel Fedin (5):
>   target-arm: Add mp-affinity property for ARM CPU class
>   hw/intc/arm_gicv3: Add state information
>   hw/intc/arm_gicv3: Add vmstate descriptors
>   NOT-FOR-UPSTREAM: kernel: Add definitions for GICv3 attributes
>   RFC: hw/intc/arm_gicv3_kvm: Implement get/put functions
> 
> Peter Maydell (15):
>   migration: Define VMSTATE_UINT64_2DARRAY
>   bitops.h: Implement half-shuffle and half-unshuffle ops
>   target-arm: Define new arm_is_el3_or_mon() function
>   target-arm: Provide hook to tell GICv3 about changes of security state
>   hw/intc/arm_gicv3: Move irq lines into GICv3CPUState structure
>   hw/intc/arm_gicv3: Implement functions to identify next pending irq
>   hw/intc/arm_gicv3: Wire up distributor and redistributor MMIO regions
>   hw/intc/arm_gicv3: Implement gicv3_set_irq()
>   hw/intc/arm_gicv3: Implement GICv3 CPU interface registers
>   hw/intc/arm_gicv3: Implement gicv3_cpuif_update()
>   hw/intc/arm_gicv3: Implement CPU i/f SGI generation registers
>   hw/intc/arm_gicv3: Add IRQ handling CPU interface registers
>   target-arm/machine.c: Allow user to request GICv3 emulation
>   target-arm/monitor.c: Advertise emulated GICv3 in capabilities
>   hw/intc/arm_gicv3: Work around Linux assuming interrupts are group 1
> 
> Shlomo Pongratz (3):
>   hw/intc/arm_gicv3: ARM GICv3 device framework
>   hw/intc/arm_gicv3: Implement GICv3 distributor registers
>   hw/intc/arm_gicv3: Implement GICv3 redistributor registers
> 
Hi Peter, I have gone through these patches. I think I don't have
further comments. Sorry that I just reviewed the patches while studying
the SPEC, so there are only few problems I found(on the hand your
patches are good:) ). I hope I'll give effective comments on the next
version.

Thanks,
-- 
Shannon