Re: [PATCH] PCI/MSI: Handle the NOMASK flag correctly for all PCI/MSI backends

[Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

On Wed, Mar 26 2025 at 13:09, Jürgen Groß wrote:
> On 26.03.25 13:05, Thomas Gleixner wrote:
>> The conversion of the XEN specific global variable pci_msi_ignore_mask to a
>> MSI domain flag, missed the facts that:
>> 
>>      1) Legacy architectures do not provide a interrupt domain
>>      2) Parent MSI domains do not necessarily have a domain info attached
>>     
>> Both cases result in an unconditional NULL pointer dereference.
>> 
>> Cure this by using the existing pci_msi_domain_supports() helper, which
>> handles all possible cases correctly.
>> 
>> Fixes: c3164d2e0d18 ("PCI/MSI: Convert pci_msi_ignore_mask to per MSI domain 
>> flag")
>> Reported-by: Daniel Gomez <da.gomez@xxxxxxxxxx>
>> Reported-by: Borislav Petkov <bp@xxxxxxxxx>
>> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>> Tested-by: Borislav Petkov <bp@xxxxxxxxx>
>> Tested-by: Daniel Gomez <da.gomez@xxxxxxxxxx>
>
> As the patch introducing the problem went in via the Xen tree, should
> this fix go in via the Xen tree, too?

I'll queue it up now and send Linus a pull request.