Re: [PATCH v2 15/24] hw/arm/tegra241-cmdqv: map VINTF page0 MMIO region

[Nicolin Chen <nicolinc@nvidia.com>]

On Fri, Feb 06, 2026 at 02:48:14PM +0000, Shameer Kolothum wrote:
> +static void tegra241_cmdqv_map_vintf_page0(Tegra241CMDQV *cmdqv)
> +{
> +    char *name;
> +
> +    if (cmdqv->vintf_page0_mapped) {
> +        return;
> +    }
> +
> +    name = g_strdup_printf("%s vintf-page0",
> +                           memory_region_name(&cmdqv->mmio_cmdqv));
> +    memory_region_init_ram_device_ptr(&cmdqv->mmio_vintf_page0,
> +                                      memory_region_owner(&cmdqv->mmio_cmdqv),
> +                                      name, VINTF_REG_PAGE_SIZE,
> +                                      cmdqv->vintf_page0);
> +    memory_region_add_subregion_overlap(&cmdqv->mmio_cmdqv, 0x30000,
> +                                        &cmdqv->mmio_vintf_page0, 1);

I wonder if you see this:

[    0.853123] arm-smmu-v3 arm-smmu-v3.0.auto: allocated 524288 entries for vcmdq0
[    0.854739] arm-smmu-v3 arm-smmu-v3.0.auto: allocated 524288 entries for vcmdq1
iommufd_backend_alloc_vdev  iommufd=142 dev_id=1 viommu_id=4 virt_id=0x200 vdev_id=8 (0)
iommufd_cdev_attach_ioas_hwpt  [iommufd=142] Successfully attached device 0009:01:00.0 (143) to id=6
smmuv3_accel_install_ste vSID=0x200 ste type=bypass hwpt_id=0x6
iommufd_viommu_alloc_eventq  iommufd=142 viommu_id=4 type=1 veventq_id=9 veventq_fd=153 (0)
iommufd_backend_alloc_hw_queue  iommufd=142 viommu_id=4 queue_type=1 index=0 addr=0xe2000000 size=0x800000 queue_id=10 (0)
vfio_listener_region_add_ram region_add [ram] 0xc0b0000 - 0xc0bffff [0xfffff7f00000]
iommufd_backend_map_dma  iommufd=142 ioas=2 iova=0xc0b0000 size=0x10000 addr=0xfffff7f00000 readonly=0 (-1)
qemu-system-aarch64: warning: IOMMU_IOAS_MAP failed: Bad address, PCI BAR?
[Switching to Thread 0xffffdd7aee80 (LWP 52426)]

Thread 38 "qemu-system-aar" hit Breakpoint 2, vfio_container_region_add (bcontainer=0xaaaaaf1220a0, section=0xffffdd7ade00, cpr_remap=false) at ../hw/vfio/listener.c:620
620             error_setg(&err, "vfio_container_dma_map(%p, 0x%"HWADDR_PRIx", "
(gdb) bt
#0  vfio_container_region_add (bcontainer=0xaaaaaf1220a0, section=0xffffdd7ade00, cpr_remap=false) at ../hw/vfio/listener.c:620
#1  0x0000aaaaab8a9290 in vfio_listener_region_add (listener=0xaaaaaf1220d0, section=0xffffdd7ade00) at ../hw/vfio/listener.c:492
#2  0x0000aaaaab3035f8 in address_space_update_topology_pass (as=0xaaaaaefa6de0, old_view=0xffffec5171b0, new_view=0xffffc8001410, adding=true) at ../system/memory.c:1030
#3  0x0000aaaaab303974 in address_space_set_flatview (as=0xaaaaaefa6de0) at ../system/memory.c:1106
#4  0x0000aaaaab303bd4 in memory_region_transaction_commit () at ../system/memory.c:1158
#5  0x0000aaaaab3084e0 in memory_region_update_container_subregions (subregion=0xaaaaaefa7b00) at ../system/memory.c:2653
#6  0x0000aaaaab3085a0 in memory_region_add_subregion_common (mr=0xaaaaaefa79e0, offset=196608, subregion=0xaaaaaefa7b00) at ../system/memory.c:2668
#7  0x0000aaaaab308644 in memory_region_add_subregion_overlap (mr=0xaaaaaefa79e0, offset=196608, subregion=0xaaaaaefa7b00, priority=1) at ../system/memory.c:2685
#8  0x0000aaaaab570f68 in tegra241_cmdqv_map_vintf_page0 (cmdqv=0xaaaaaefa79c0) at ../hw/arm/tegra241-cmdqv.c:275
#9  0x0000aaaaab571188 in tegra241_cmdqv_setup_vcmdq (cmdqv=0xaaaaaefa79c0, index=0, errp=0xffffdd7ae0e8) at ../hw/arm/tegra241-cmdqv.c:317
#10 0x0000aaaaab571550 in tegra241_cmdqv_write_vcmdq (cmdqv=0xaaaaaefa79c0, offset0=131072, index=0, value=3791650835, size=4, errp=0xffffdd7ae0e8) at ../hw/arm/tegra241-cmdqv.c:378
#11 0x0000aaaaab571a60 in tegra241_cmdqv_write (opaque=0xaaaaaefa79c0, offset=131072, value=3791650835, size=4) at ../hw/arm/tegra241-cmdqv.c:484

Nicolin