[PATCH 1/3] PCI: vmd: Correct PCI Header Type Register's MFD bit check

From: Ilpo Järvinen
Date: Tue Oct 03 2023 - 08:53:35 EST


vmd_domain_reset() attempts to find whether the device may contain
multiple functions by checking 0x80 (Multi-Function Device), however,
the hdr_type variable has already been masked with PCI_HEADER_TYPE_MASK
so the check can never true.

To fix the issue, don't mask the read with PCI_HEADER_TYPE_MASK.

Fixes: 6aab5622296b ("PCI: vmd: Clean up domain before enumeration")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Cc: Nirmal Patel <nirmal.patel@xxxxxxxxxxxxxxx>
---
drivers/pci/controller/vmd.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index e718a816d481..d5b97a6aae56 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -525,8 +525,7 @@ static void vmd_domain_reset(struct vmd_dev *vmd)
base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus,
PCI_DEVFN(dev, 0), 0);

- hdr_type = readb(base + PCI_HEADER_TYPE) &
- PCI_HEADER_TYPE_MASK;
+ hdr_type = readb(base + PCI_HEADER_TYPE);

functions = (hdr_type & 0x80) ? 8 : 1;
for (fn = 0; fn < functions; fn++) {
--
2.30.2