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Date: Tue, 7 May 2024 20:40:23 +0530
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Subject: Re: [RFC PATCH v2 0/6] powerpc: pSeries: vfio: iommu: Re-enable
 support for SPAPR TCE VFIO
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To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Alexey Kardashevskiy <aik@amd.com>, mpe@ellerman.id.au,
        tpearson@raptorengineering.com, alex.williamson@redhat.com,
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        kvm@vger.kernel.org, msuchanek@suse.de, oohall@gmail.com,
        mahesh@linux.ibm.com, jroedel@suse.de, vaibhav@linux.ibm.com,
        svaidy@linux.ibm.com
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From: Shivaprasad G Bhat <sbhat@linux.ibm.com>
In-Reply-To: <20240506174357.GF901876@ziepe.ca>
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Hi Jason,


On 5/6/24 23:13, Jason Gunthorpe wrote:
> On Sat, May 04, 2024 at 12:33:53AM +0530, Shivaprasad G Bhat wrote:
>> We have legacy workloads using VFIO in userspace/kvm guests running
>> on downstream distro kernels. We want these workloads to be able to
>> continue running on our arch.
> It has been broken since 2018, I don't find this reasoning entirely
> reasonable :\

Though upstream has been broken since 2018 for pSeries, the breaking

patches got trickled into downstream distro kernels only in the last few

years. The legacy workloads that were running on PowerNV with these

downstream distros are now broken on the pSeries logical partitions

without the fixes in this series.

>> I firmly believe the refactoring in this patch series is a step in
>> that direction.
> But fine, as long as we are going to fix it. PPC really needs this to
> be resolved to keep working.

Thanks, We are working on it.


Regards,

Shivaprasad

>
> Jason