Re: [patch 3/8] PCI/MSI: Enforce that MSI-X table entry is masked for update

[Thomas Gleixner]

Ashok,

On Wed, Jul 21 2021 at 15:32, Ashok Raj wrote:
> On Wed, Jul 21, 2021 at 09:11:29PM +0200, Thomas Gleixner wrote:
>> +		/*
>> +		 * The specification mandates that the entry is masked
>> +		 * when the message is modified:
>> +		 *
>> +		 * "If software changes the Address or Data value of an
>> +		 * entry while the entry is unmasked, the result is
>> +		 * undefined."
>> +		 */
>> +		if (unmasked)
>> +			__pci_msix_desc_mask_irq(entry, PCI_MSIX_ENTRY_CTRL_MASKBIT);
>> +
>
> Is there any locking needs here? say during cpu hotplug and some user-space
> setting affinity?

No. Except for suspend/resume this is always serialized by irq_desc::lock().

Thanks,

        tglx