On 10/17/2025 11:43 AM, Sairaj Kodilkar wrote:
This series provide fixes for following two issues:

1. AMD IOMMU fails to detect the devices when they are attached to PCI bus with
    bus id != 0.
    e.g. With following command line, dhclient command fails inside the guest

     -device 
pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x5
 \
     -netdev user,id=USER0,hostfwd=tcp::3333-:22 \
     -device 
virtio-net-pci,id=vnet0,iommu_platform=on,disable-legacy=on,romfile=,netdev=USER0,bus=pci.1,addr=0
 \

2. Current AMD IOMMU supports IOVAs upto 60 bit which cause failure while
    setting up the devices when guest is booted with command line
    "iommu.forcedac=1".

    One example of the failure is when there are two virtio ethernet devices
    attached to the guest with command line
-netdev user,id=USER0 \
        -netdev user,id=USER1 \
        -device 
virtio-net-pci,id=vnet0,iommu_platform=on,disable-legacy=on,romfile=,netdev=USER0
 \
        -device 
virtio-net-pci,id=vnet1,iommu_platform=on,disable-legacy=on,romfile=,netdev=USER1
 \
In this case dhclient fails for second device with following dmesg [ 24.802644] virtio_net virtio0 enp0s1: TX timeout on queue: 0, sq: output.0, vq: 0x1, name: output.0, 5664000 usecs ago
    [   29.856716] virtio_net virtio0 enp0s1: NETDEV WATCHDOG: CPU: 59: 
transmit queue 0 timed out 10720 ms
    [   29.858585] virtio_net virtio0 enp0s1: TX timeout on queue: 0, sq: 
output.0, vq: 0x1, name: output.0, 10720000 usecs ago

-------------------------------------------------------------------------------

Change log:
----------

* Changes since V2:
https://lore.kernel.org/qemu-devel/[email protected]/
P1:
  - Remove cast from the pointer assignment [MST]
  - Rename struct amdvi_as_key to AMDViAsKey [Alejandro, MST]
  - Fix compilation error due to missing 'static' [Alejandro]

P2:
  - Rename struct amdvi_iotlb_key to AMDViIOTLBKey [Alejandro, MST]
  - Fix compilation error [Alejandro]

Correction...
This is AMDVIAskey and AMDVIIOTLBKey, not AMDViAsKey and AMDViIOTLBKey

Thanks
Sairaj

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