* [PATCH] PCI/MSI: Initialize the prepare descriptor by default
@ 2025-07-08 5:18 Naman Jain
2025-07-08 10:02 ` Shradha Gupta
0 siblings, 1 reply; 5+ messages in thread
From: Naman Jain @ 2025-07-08 5:18 UTC (permalink / raw)
To: Bjorn Helgaas, Thomas Gleixner, Marc Zyngier, Lorenzo Pieralisi,
Shivamurthy Shastri, Shradha Gupta
Cc: Naman Jain, linux-pci, linux-kernel, linux-hyperv, Roman Kisel
Plug the default MSI-X prepare descriptor for non-implemented ops by
default to workaround the inability of Hyper-V vPCI module to setup
the MSI-X descriptors properly; especially for dynamically allocated
MSI-X.
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
---
drivers/pci/msi/irqdomain.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
index 765312c92d9b..655e99b9c8cc 100644
--- a/drivers/pci/msi/irqdomain.c
+++ b/drivers/pci/msi/irqdomain.c
@@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
} else {
if (ops->set_desc == NULL)
ops->set_desc = pci_msi_domain_set_desc;
+ if (ops->prepare_desc == NULL)
+ ops->prepare_desc = pci_msix_prepare_desc;
}
}
base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
--
2.34.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] PCI/MSI: Initialize the prepare descriptor by default
2025-07-08 5:18 [PATCH] PCI/MSI: Initialize the prepare descriptor by default Naman Jain
@ 2025-07-08 10:02 ` Shradha Gupta
2025-07-08 10:15 ` Naman Jain
0 siblings, 1 reply; 5+ messages in thread
From: Shradha Gupta @ 2025-07-08 10:02 UTC (permalink / raw)
To: Naman Jain
Cc: Bjorn Helgaas, Thomas Gleixner, Marc Zyngier, Lorenzo Pieralisi,
Shivamurthy Shastri, linux-pci, linux-kernel, linux-hyperv,
Roman Kisel
On Tue, Jul 08, 2025 at 10:48:48AM +0530, Naman Jain wrote:
> Plug the default MSI-X prepare descriptor for non-implemented ops by
> default to workaround the inability of Hyper-V vPCI module to setup
> the MSI-X descriptors properly; especially for dynamically allocated
> MSI-X.
>
> Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
> ---
> drivers/pci/msi/irqdomain.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
> index 765312c92d9b..655e99b9c8cc 100644
> --- a/drivers/pci/msi/irqdomain.c
> +++ b/drivers/pci/msi/irqdomain.c
> @@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
> } else {
> if (ops->set_desc == NULL)
> ops->set_desc = pci_msi_domain_set_desc;
> + if (ops->prepare_desc == NULL)
> + ops->prepare_desc = pci_msix_prepare_desc;
> }
> }
>
>
> base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
> --
> 2.34.1
>
Hey Naman,
can you please try your tests with this patch:
https://lore.kernel.org/all/1749651015-9668-1-git-send-email-shradhagupta@linux.microsoft.com/
I think this should help your use case
Regards,
Shradha.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] PCI/MSI: Initialize the prepare descriptor by default
2025-07-08 10:02 ` Shradha Gupta
@ 2025-07-08 10:15 ` Naman Jain
2025-07-08 16:08 ` Bjorn Helgaas
0 siblings, 1 reply; 5+ messages in thread
From: Naman Jain @ 2025-07-08 10:15 UTC (permalink / raw)
To: Shradha Gupta
Cc: Bjorn Helgaas, Thomas Gleixner, Marc Zyngier, Lorenzo Pieralisi,
Shivamurthy Shastri, linux-pci, linux-kernel, linux-hyperv,
Roman Kisel
On 7/8/2025 3:32 PM, Shradha Gupta wrote:
> On Tue, Jul 08, 2025 at 10:48:48AM +0530, Naman Jain wrote:
>> Plug the default MSI-X prepare descriptor for non-implemented ops by
>> default to workaround the inability of Hyper-V vPCI module to setup
>> the MSI-X descriptors properly; especially for dynamically allocated
>> MSI-X.
>>
>> Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
>> ---
>> drivers/pci/msi/irqdomain.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
>> index 765312c92d9b..655e99b9c8cc 100644
>> --- a/drivers/pci/msi/irqdomain.c
>> +++ b/drivers/pci/msi/irqdomain.c
>> @@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
>> } else {
>> if (ops->set_desc == NULL)
>> ops->set_desc = pci_msi_domain_set_desc;
>> + if (ops->prepare_desc == NULL)
>> + ops->prepare_desc = pci_msix_prepare_desc;
>> }
>> }
>>
>>
>> base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
>> --
>> 2.34.1
>>
>
> Hey Naman,
>
> can you please try your tests with this patch:
> https://lore.kernel.org/all/1749651015-9668-1-git-send-email-shradhagupta@linux.microsoft.com/
> I think this should help your use case
>
> Regards,
> Shradha.
Hey,
Thanks for sharing this, this works for me.
Closing this thread.
Regards,
Naman
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] PCI/MSI: Initialize the prepare descriptor by default
2025-07-08 10:15 ` Naman Jain
@ 2025-07-08 16:08 ` Bjorn Helgaas
2025-07-09 4:42 ` Naman Jain
0 siblings, 1 reply; 5+ messages in thread
From: Bjorn Helgaas @ 2025-07-08 16:08 UTC (permalink / raw)
To: Naman Jain
Cc: Shradha Gupta, Bjorn Helgaas, Thomas Gleixner, Marc Zyngier,
Lorenzo Pieralisi, Shivamurthy Shastri, linux-pci, linux-kernel,
linux-hyperv, Roman Kisel
On Tue, Jul 08, 2025 at 03:45:05PM +0530, Naman Jain wrote:
> On 7/8/2025 3:32 PM, Shradha Gupta wrote:
> > On Tue, Jul 08, 2025 at 10:48:48AM +0530, Naman Jain wrote:
> > > Plug the default MSI-X prepare descriptor for non-implemented ops by
> > > default to workaround the inability of Hyper-V vPCI module to setup
> > > the MSI-X descriptors properly; especially for dynamically allocated
> > > MSI-X.
> > >
> > > Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
> > > ---
> > > drivers/pci/msi/irqdomain.c | 2 ++
> > > 1 file changed, 2 insertions(+)
> > >
> > > diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
> > > index 765312c92d9b..655e99b9c8cc 100644
> > > --- a/drivers/pci/msi/irqdomain.c
> > > +++ b/drivers/pci/msi/irqdomain.c
> > > @@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
> > > } else {
> > > if (ops->set_desc == NULL)
> > > ops->set_desc = pci_msi_domain_set_desc;
> > > + if (ops->prepare_desc == NULL)
> > > + ops->prepare_desc = pci_msix_prepare_desc;
> > > }
> > > }
> > >
> > > base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
> > > --
> > > 2.34.1
> > >
> >
> > Hey Naman,
> >
> > can you please try your tests with this patch:
> > https://lore.kernel.org/all/1749651015-9668-1-git-send-email-shradhagupta@linux.microsoft.com/
> > I think this should help your use case
>
> Hey,
> Thanks for sharing this, this works for me.
>
> Closing this thread.
I guess this means we should ignore this patch? If it turns out that
we do need this patch, I'd like to add some details in the commit log
about what this problem looks like to users.
Bjorn
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] PCI/MSI: Initialize the prepare descriptor by default
2025-07-08 16:08 ` Bjorn Helgaas
@ 2025-07-09 4:42 ` Naman Jain
0 siblings, 0 replies; 5+ messages in thread
From: Naman Jain @ 2025-07-09 4:42 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: Shradha Gupta, Bjorn Helgaas, Thomas Gleixner, Marc Zyngier,
Lorenzo Pieralisi, Shivamurthy Shastri, linux-pci, linux-kernel,
linux-hyperv, Roman Kisel
On 7/8/2025 9:38 PM, Bjorn Helgaas wrote:
> On Tue, Jul 08, 2025 at 03:45:05PM +0530, Naman Jain wrote:
>> On 7/8/2025 3:32 PM, Shradha Gupta wrote:
>>> On Tue, Jul 08, 2025 at 10:48:48AM +0530, Naman Jain wrote:
>>>> Plug the default MSI-X prepare descriptor for non-implemented ops by
>>>> default to workaround the inability of Hyper-V vPCI module to setup
>>>> the MSI-X descriptors properly; especially for dynamically allocated
>>>> MSI-X.
>>>>
>>>> Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
>>>> ---
>>>> drivers/pci/msi/irqdomain.c | 2 ++
>>>> 1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
>>>> index 765312c92d9b..655e99b9c8cc 100644
>>>> --- a/drivers/pci/msi/irqdomain.c
>>>> +++ b/drivers/pci/msi/irqdomain.c
>>>> @@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
>>>> } else {
>>>> if (ops->set_desc == NULL)
>>>> ops->set_desc = pci_msi_domain_set_desc;
>>>> + if (ops->prepare_desc == NULL)
>>>> + ops->prepare_desc = pci_msix_prepare_desc;
>>>> }
>>>> }
>>>>
>>>> base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
>>>> --
>>>> 2.34.1
>>>>
>>>
>>> Hey Naman,
>>>
>>> can you please try your tests with this patch:
>>> https://lore.kernel.org/all/1749651015-9668-1-git-send-email-shradhagupta@linux.microsoft.com/
>>> I think this should help your use case
>>
>> Hey,
>> Thanks for sharing this, this works for me.
>>
>> Closing this thread.
>
> I guess this means we should ignore this patch? If it turns out that
> we do need this patch, I'd like to add some details in the commit log
> about what this problem looks like to users.
>
> Bjorn
Yes, my patch is no longer required, since it was doing the same thing
that Shradha's patch (1-2) were doing, but in a different way. Shradha's
patch is better and would suffice for the use case. Please ignore this
patch.
Thanks.
Regards,
Naman
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2025-07-09 4:42 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2025-07-08 5:18 [PATCH] PCI/MSI: Initialize the prepare descriptor by default Naman Jain
2025-07-08 10:02 ` Shradha Gupta
2025-07-08 10:15 ` Naman Jain
2025-07-08 16:08 ` Bjorn Helgaas
2025-07-09 4:42 ` Naman Jain
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