Re: [Qemu-devel] [PATCH 2/2] x86_iommu: check if machine has PCI bus

[Peter Xu <peterx@redhat.com>]

On Fri, Sep 15, 2017 at 01:13:46PM +0200, Mohammed Gamal wrote:
> Starting qemu with
> qemu-system-x86_64 -S -M isapc -device {amd|intel}-iommu
> leads to a segfault. The code assume PCI bus is present and
> tries to access the bus structure without checking.
> 
> Since Intel VT-d and AMDVI should only work with PCI, add a
> check for PCI bus and return error if not present.
> 
> Signed-off-by: Mohammed Gamal <mgamal@redhat.com>

Reviewed-by: Peter Xu <peterx@redhat.com>

> ---
>  hw/i386/x86-iommu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
> index 4d17e1f..afd8cd9 100644
> --- a/hw/i386/x86-iommu.c
> +++ b/hw/i386/x86-iommu.c
> @@ -88,7 +88,7 @@ static void x86_iommu_realize(DeviceState *dev, Error **errp)
>          PC_MACHINE(object_dynamic_cast(OBJECT(ms), TYPE_PC_MACHINE));
>      QLIST_INIT(&x86_iommu->iec_notifiers);
>  
> -    if (!pcms) {
> +    if (!pcms || !pcms->bus) {
>          error_setg(errp, "Machine-type '%s' not supported by iommu",
>                     mc->name);
>          return;
> -- 
> 1.8.3.1
> 

-- 
Peter Xu