Re: [PATCH v2 0/2] amd_iommu: Cleanups and fixes (PART 2)

[Sairaj Kodilkar <sarunkod@amd.com>]

On 10/15/2025 2:57 AM, Alejandro Jimenez wrote:
> 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.

Hi Alejandro,
Yep I did that, but I think that somehow I tested a different branch 
thats why failed to catch these errors.
Sorry for inconvenience. Will take care of it in future !

Thanks
Sairaj

>
> 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(-)
>>
>