[PATCH v5 0/2] RISC-V: KVM: Convert HGEI management to fully per-HART

[Anup Patel]

On Mon, May 25, 2026 at 3:19 PM Anup Patel <anup.patel at oss.qualcomm.com> wrote:
>
> From: "Guo Ren (Alibaba DAMO Academy)" <guoren at kernel.org>
>
> This short series converts RISC-V KVM AIA's Hypervisor Guest External
> Interrupt (HGEI) line management from a global "one-size-fits-all"
> model to a fully per-HART (per-CPU) model. It also performs the
> corresponding changes in the IMSIC irqchip driver.
>
> The motivation is to properly support heterogeneous RISC-V SoCs
> (big.LITTLE, multi-vendor core mixes) where different HARTs may
> expose different numbers of guest interrupt files / HGEIE bits.
>
> After this series, HGEI allocation, freeing, and interrupt delivery
> are completely per-HART and there are no remaining global assumptions
> about number of guest interrupt files.
>
> Changelog:
> V5:
>  - Avoid re-initializing hgctrl->lock in kvm_riscv_aia_enable()
>  - Setup free_bitmap only once in kvm_riscv_aia_enable()
>  - Make kvm_riscv_aia_nr_hgei so that it can be concurrently
>    updated from kvm_riscv_aia_enable()
>
> V4:
>  - Don't modify kvm_riscv_aia_nr_hgei in kvm_riscv_aia_enable()
>    since we use kvm_riscv_aia_nr_hgei mostly for HGEI enable/disable
>    checks.
>  - Use GENMASK_ULL() instead of `BIT(hgctrl->nr_hgei + 1) - 1`
>  - Always setup SGEI interrupt irrespective of kvm_riscv_aia_nr_hgei
>
> V3:
>  - Move PATCH3 as first patch and kept the nr_guest_files in
>    global config as the number of guest files across all CPUs
>  - Droped original PATCH2 and squashed original PATCH4 into
>    original PATCH1 which is now PATCH2.
>  - Addressed comments in original PATCH1.
>
> V2:
>  - Add per-HART IMSIC guest files to compute final HGEI count.
>  - Add min(local->nr_guest_files, nr_guest_files);
>
> V1:
>  - https://lore.kernel.org/kvm-riscv/20260421145451.1597930-1-guoren@kernel.org/
>
> Guo Ren (Alibaba DAMO Academy) (2):
>   irqchip/riscv-imsic: Add nr_guest_files in per-HART local config
>   RISC-V: KVM: AIA: Make HGEI number management fully per-CPU
>
>  arch/riscv/include/asm/kvm_aia.h        |  2 +-
>  arch/riscv/kvm/aia.c                    | 88 +++++++++++++++----------
>  arch/riscv/kvm/aia_device.c             |  4 +-
>  arch/riscv/kvm/main.c                   |  8 +--
>  drivers/irqchip/irq-riscv-imsic-state.c |  9 ++-
>  include/linux/irqchip/riscv-imsic.h     |  5 +-
>  6 files changed, 68 insertions(+), 48 deletions(-)
>
> --
> 2.43.0
>

Queued this series for Linux-7.2

Thanks,
Anup