[PATCH] PCI/MSI: msix_setup_msi_descs: Restore logic for msi_attrib.can_mask

[Josef Johansson <josef@xxxxxxxxxxx>]

From: Josef Johansson <josef@xxxxxxxxxxx>

PCI/MSI: msix_setup_msi_descs: Restore logic for msi_attrib.can_mask
    
Commit 71020a3c0dff4 ("PCI/MSI: Use msi_add_msi_desc()") modifies
the logic of checking msi_attrib.can_mask, without any reason.
    
This commits restores that logic.

Fixes: 71020a3c0dff4 ("PCI/MSI: Use msi_add_msi_desc()")
Signed-off-by: Josef Johansson <josef@xxxxxxxxxxx>

---
Trying to fix a NULL BUG in the NVMe MSIX implementation I stumbled upon this code,
which ironically was what my last MSI patch resulted into.

I don't see any reason why this logic was change, nor do I have the possibility
to see if anything works with my patch or without, since the kernel crashes
in other places.

As such this is still untested, but as far as I can tell it should restore
functionality.

CC xen-devel since it very much relates to Xen kernel (via pci_msi_ignore_mask).
---

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index c19c7ca58186..146e7b9a01cc 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -526,7 +526,7 @@ static int msix_setup_msi_descs(struct pci_dev *dev, void __iomem *base,
 		desc.pci.msi_attrib.can_mask = !pci_msi_ignore_mask &&
 					       !desc.pci.msi_attrib.is_virtual;
 
-		if (!desc.pci.msi_attrib.can_mask) {
+		if (desc.pci.msi_attrib.can_mask) {
 			addr = pci_msix_desc_addr(&desc);
 			desc.pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);
 		}

--
2.31.1