The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 16b8fe4caf499ae8e12d2ab1b1324497e36a7b83 Mon Sep 17 00:00:00 2001
From: Eric Auger <eric.auger@xxxxxxxxxx>
Date: Fri, 13 Nov 2020 18:52:02 +0100
Subject: [PATCH] vfio/pci: Move dummy_resources_list init in vfio_pci_probe()
In case an error occurs in vfio_pci_enable() before the call to
vfio_pci_probe_mmaps(), vfio_pci_disable() will try to iterate
on an uninitialized list and cause a kernel panic.
Lets move to the initialization to vfio_pci_probe() to fix the
issue.
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Fixes: 05f0c03fbac1 ("vfio-pci: Allow to mmap sub-page MMIO BARs if the mmio page is exclusive")
CC: Stable <stable@xxxxxxxxxxxxxxx> # v4.7+
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index e6190173482c..47ebc5c49ca4 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -161,8 +161,6 @@ static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
int i;
struct vfio_pci_dummy_resource *dummy_res;
- INIT_LIST_HEAD(&vdev->dummy_resources_list);
-
for (i = 0; i < PCI_STD_NUM_BARS; i++) {
int bar = i + PCI_STD_RESOURCES;
@@ -1966,6 +1964,7 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
mutex_init(&vdev->igate);
spin_lock_init(&vdev->irqlock);
mutex_init(&vdev->ioeventfds_lock);
+ INIT_LIST_HEAD(&vdev->dummy_resources_list);
INIT_LIST_HEAD(&vdev->ioeventfds_list);
mutex_init(&vdev->vma_lock);
INIT_LIST_HEAD(&vdev->vma_list);
