Hi,

On 10/13/25 1:00 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: > ----------
P1:

I generally like to include a link to the previous version. Not a must, but makes it easier others to follow the series history.

  - Use fixed type uint8_t for devfn
  - Use uintptr_t instead of uint64_t
  - Build hash key using lower 56 bits of bus pointer and 8 bits of devfn
  - Use gboolean instead of int for amdvi_find_as_by_devid
  - Update comments
  - Use IOMMU_NOTIFIER_NONE instead of IOMMU_NONE

P2:
  - Reword commit message
  - Correctly initialize `struct amdvi_iotlb_key`
  - Remove unused macro


Before sending a new revision, ideally you should run a smoke test (or more thorough testing depending on the scope of the changes). But at the bare minimum please make sure a clean build is done. There are trivial issues in both patches that cause compilation errors. See the replies for details.

Thank you,
Alejandro

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

Base commit: (qemu uptream) eb7abb4a719f

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

Sairaj Kodilkar (2):
   amd_iommu: Fix handling device on buses != 0
   amd_iommu: Support 64 bit address for IOTLB lookup

  hw/i386/amd_iommu.c | 179 +++++++++++++++++++++++++++-----------------
  hw/i386/amd_iommu.h |   6 +-
  2 files changed, 113 insertions(+), 72 deletions(-)



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