Instead of a 32-bit/64-bit dichotomy, check the MSI address against
msi_addr_mask.

This allows platforms with MSI doorbell above 32-bit address space to
work with devices without full 64-bit MSI address support, as long as
the doorbell is within addressable range of MSI of the device.

Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>

---
v3: %llx -> %#llx (Bjorn)
---
 drivers/pci/msi/msi.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index 48f5f03d1479..77713f89a10b 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -321,14 +321,17 @@ static int msi_setup_msi_desc(struct pci_dev *dev, int nvec,
 static int msi_verify_entries(struct pci_dev *dev)
 {
 	struct msi_desc *entry;
+	u64 address;
 
 	if (dev->msi_addr_mask == DMA_BIT_MASK(64))
 		return 0;
 
 	msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
-		if (entry->msg.address_hi) {
-			pci_err(dev, "arch assigned 64-bit MSI address %#x%08x but device only supports 32 bits\n",
-				entry->msg.address_hi, entry->msg.address_lo);
+		address = (u64)entry->msg.address_hi << 32 |
+			  entry->msg.address_lo;
+		if (address & ~dev->msi_addr_mask) {
+			pci_err(dev, "arch assigned 64-bit MSI address %#llx above device MSI address mask %#llx\n",
+				address, dev->msi_addr_mask);
 			break;
 		}
 	}

-- 
2.52.0

On Fri, Jan 23 2026 at 14:07, Vivian Wang wrote:
> Instead of a 32-bit/64-bit dichotomy, check the MSI address against
> msi_addr_mask.
>
> This allows platforms with MSI doorbell above 32-bit address space to

with a MSI doorbell address above the 32-bit limit to

> work with devices without full 64-bit MSI address support, as long as
> the doorbell is within addressable range of MSI of the device.

within the addressable

>  static int msi_verify_entries(struct pci_dev *dev)
>  {
>  	struct msi_desc *entry;
> +	u64 address;
>  
>  	if (dev->msi_addr_mask == DMA_BIT_MASK(64))
>  		return 0;
>  
>  	msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
> -		if (entry->msg.address_hi) {
> -			pci_err(dev, "arch assigned 64-bit MSI address %#x%08x but device only supports 32 bits\n",
> -				entry->msg.address_hi, entry->msg.address_lo);
> +		address = (u64)entry->msg.address_hi << 32 |
> +			  entry->msg.address_lo;

No line break required. Let it stick out.

> +		if (address & ~dev->msi_addr_mask) {
> +			pci_err(dev, "arch assigned 64-bit MSI address %#llx above device MSI address mask %#llx\n",
> +				address, dev->msi_addr_mask);
>  			break;
>  		}
>  	}

Other than those nits:

Reviewed-by: Thomas Gleixner <tglx@kernel.org>

Hi Thomas,

On 1/27/26 17:27, Thomas Gleixner wrote:
> [...]
>
> Other than those nits:
>
> Reviewed-by: Thomas Gleixner <tglx@kernel.org>

I will fix these and patch 1 as well in v4. Thanks for your review.

Vivian "dramforever" Wang