The following commit has been merged into the irq/msi branch of tip:

Commit-ID:     52f0d862f595a2fa18ef44532619a080c24fe4cb
Gitweb:        https://git.kernel.org/tip/52f0d862f595a2fa18ef44532619a080c24fe4cb
Author:        Vivian Wang <wangruikang@iscas.ac.cn>
AuthorDate:    Thu, 29 Jan 2026 09:56:07 +08:00
Committer:     Thomas Gleixner <tglx@kernel.org>
CommitterDate: Sat, 31 Jan 2026 01:11:48 +01:00

PCI/MSI: Check the device specific address mask in msi_verify_entries()

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

This allows platforms with an 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 the addressable range of the device.

[ tglx: Massaged changelog ]

Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260129-pci-msi-addr-mask-v4-2-70da998f2750@iscas.ac.cn
---
 drivers/pci/msi/msi.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index fb9a42b..e241217 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -321,14 +321,16 @@ 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;
 		}
 	}