Re: [PATCH V0] iommu/hyperv: Create hyperv subdirectory under iommu

[Mukesh R]

On 5/26/26 08:59, Yu Zhang wrote:
> On Mon, May 25, 2026 at 06:20:37PM -0700, Mukesh R wrote:
> > Create hyperv subdirectory under drivers/iommu in anticipation of more
> > hyperv related files for upcoming PCI passthru and pv IOMMU patches.
> > Also, the current file hyperv-iommu.c actually implements irq remapping,
> > so rename to more appropriate hv-irq-remap.c and move it under the new
> > hyperv subdirectory. Lastly, this file should not be tied to
> > CONFIG_HYPERV_IOMMU, but to CONFIG_HYPERV and CONFIG_IRQ_REMAP.
>
> Thanks for this pathch, Mukesh!
>
> Jason raised a question about whether Hyper-V's IRQ remapping file belongs
> under drivers/iommu/hyperv/ at all, since unlike Intel/AMD, Hyper-V's IRQ
> remapping is not co-mingled with the IOMMU hardware:
>
> 	https://lore.kernel.org/all/20260520133807.GS7702@xxxxxxxx/
>
> Though we don't end up moving it elsewhere (the IRQ remapping framework
> and its internal header, irq_remapping.h, live under drivers/iommu/, and
> all existing backends sit alongside them), it would be good to acknowledge
> this in the commit message and explain the rationale,

Ok. Also, I missed the Kconfig file, will send V1.

Thanks,
-Mukesh

> > Signed-off-by: Mukesh R <mrathor@xxxxxxxxxxxxxxxxxxx>
> > ---
> >   MAINTAINERS                                             | 2 +-
> >   drivers/iommu/Makefile                                  | 2 +-
> >   drivers/iommu/hyperv/Makefile                           | 2 ++
> >   drivers/iommu/{hyperv-iommu.c => hyperv/hv-irq-remap.c} | 8 +-------
> >   drivers/iommu/irq_remapping.c                           | 2 +-
> >   5 files changed, 6 insertions(+), 10 deletions(-)
> >   create mode 100644 drivers/iommu/hyperv/Makefile
> >   rename drivers/iommu/{hyperv-iommu.c => hyperv/hv-irq-remap.c} (99%)
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index d1cc0e12fe1f..b651ee0c6e6b 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -11914,7 +11914,7 @@ F:	drivers/clocksource/hyperv_timer.c
> >   F:	drivers/hid/hid-hyperv.c
> >   F:	drivers/hv/
> >   F:	drivers/input/serio/hyperv-keyboard.c
> > -F:	drivers/iommu/hyperv-iommu.c
> > +F:	drivers/iommu/hyperv/hv-irq-remap.c
> >   F:	drivers/net/ethernet/microsoft/
> >   F:	drivers/net/hyperv/
> >   F:	drivers/pci/controller/pci-hyperv-intf.c
> > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
> > index 0275821f4ef9..d9683422aecb 100644
> > --- a/drivers/iommu/Makefile
> > +++ b/drivers/iommu/Makefile
> > @@ -4,6 +4,7 @@ obj-$(CONFIG_AMD_IOMMU) += amd/
> >   obj-$(CONFIG_INTEL_IOMMU) += intel/
> >   obj-$(CONFIG_RISCV_IOMMU) += riscv/
> >   obj-$(CONFIG_GENERIC_PT) += generic_pt/fmt/
> > +obj-$(CONFIG_HYPERV) += hyperv/
> >   obj-$(CONFIG_IOMMU_API) += iommu.o
> >   obj-$(CONFIG_IOMMU_SUPPORT) += iommu-pages.o
> >   obj-$(CONFIG_IOMMU_API) += iommu-traces.o
> > @@ -30,7 +31,6 @@ obj-$(CONFIG_TEGRA_IOMMU_SMMU) += tegra-smmu.o
> >   obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o
> >   obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o
> >   obj-$(CONFIG_S390_IOMMU) += s390-iommu.o
> > -obj-$(CONFIG_HYPERV_IOMMU) += hyperv-iommu.o
>
> Any reason why we are removing the CONFIG_HYPERV_IOMMU? You are leaving
> CONFIG_HYPERV_IOMMU an orphan configuration now (and also the  backward
> compatibility issue?).
>
> >   obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o
> >   obj-$(CONFIG_IOMMU_SVA) += iommu-sva.o
> >   obj-$(CONFIG_IOMMU_IOPF) += io-pgfault.o
>
> B.R.
> Yu