This is a note to let you know that I've just added the patch titled
PCI: vmd: Correct PCI Header Type Register's multi-function check
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-vmd-correct-pci-header-type-register-s-multi-fun.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c9eae9ade53c1be17707278f21149ece663ecd04
Author: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Date: Tue Oct 3 15:52:58 2023 +0300
PCI: vmd: Correct PCI Header Type Register's multi-function check
[ Upstream commit 5827e17d0555b566c32044b0632b46f9f95054fa ]
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")
Link: https://lore.kernel.org/r/20231003125300.5541-2-ilpo.jarvinen@xxxxxxxxxxxxxxx
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Nirmal Patel <nirmal.patel@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index ad56df98b8e63..1c1c1aa940a51 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++) {
