Re: [PATCH v4 23/27] hw/i386/intel_iommu: Remove IntelIOMMUState::buggy_eim field

[Igor Mammedov]

On Thu,  8 May 2025 15:35:46 +0200
Philippe Mathieu-Daudé <philmd@linaro.org> wrote:

> The IntelIOMMUState::buggy_eim boolean was only set in
> the hw_compat_2_7[] array, via the 'x-buggy-eim=true'
> property. We removed all machines using that array, lets
> remove that property, simplifying vtd_decide_config().
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  include/hw/i386/intel_iommu.h | 1 -
>  hw/i386/intel_iommu.c         | 5 ++---
>  2 files changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
> index e95477e8554..29304329d05 100644
> --- a/include/hw/i386/intel_iommu.h
> +++ b/include/hw/i386/intel_iommu.h
> @@ -303,7 +303,6 @@ struct IntelIOMMUState {
>      uint32_t intr_size;             /* Number of IR table entries */
>      bool intr_eime;                 /* Extended interrupt mode enabled */
>      OnOffAuto intr_eim;             /* Toggle for EIM cabability */
> -    bool buggy_eim;                 /* Force buggy EIM unless eim=off */
>      uint8_t aw_bits;                /* Host/IOVA address width (in bits) */
>      bool dma_drain;                 /* Whether DMA r/w draining enabled */
>      bool dma_translation;           /* Whether DMA translation supported */
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index 5f8ed1243d1..c980cecb4ee 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -3823,7 +3823,6 @@ static const Property vtd_properties[] = {
>      DEFINE_PROP_UINT32("version", IntelIOMMUState, version, 0),
>      DEFINE_PROP_ON_OFF_AUTO("eim", IntelIOMMUState, intr_eim,
>                              ON_OFF_AUTO_AUTO),
> -    DEFINE_PROP_BOOL("x-buggy-eim", IntelIOMMUState, buggy_eim, false),
>      DEFINE_PROP_UINT8("aw-bits", IntelIOMMUState, aw_bits,
>                        VTD_HOST_ADDRESS_WIDTH),
>      DEFINE_PROP_BOOL("caching-mode", IntelIOMMUState, caching_mode, FALSE),
> @@ -4731,11 +4730,11 @@ static bool vtd_decide_config(IntelIOMMUState *s, 
> Error **errp)
>      }
>  
>      if (s->intr_eim == ON_OFF_AUTO_AUTO) {
> -        s->intr_eim = (kvm_irqchip_in_kernel() || s->buggy_eim)
> +        s->intr_eim = kvm_irqchip_in_kernel()
>                        && x86_iommu_ir_supported(x86_iommu) ?
>                                                ON_OFF_AUTO_ON : 
> ON_OFF_AUTO_OFF;
>      }
> -    if (s->intr_eim == ON_OFF_AUTO_ON && !s->buggy_eim) {
> +    if (s->intr_eim == ON_OFF_AUTO_ON) {
>          if (kvm_irqchip_is_split() && !kvm_enable_x2apic()) {
>              error_setg(errp, "eim=on requires support on the KVM side"
>                               "(X2APIC_API, first shipped in v4.7)");