s390/pci: remove pdev pointer from arch data

For each PCI function we need to maintain arch specific data in
struct zpci_dev which also contains a pointer to struct pci_dev.

When a function is registered or deregistered (which is triggered by PCI
common code) we need to adjust that pointer which could interfere with
the machine check handler (triggered by FW) using zpci_dev->pdev.

Since multiple instances of the same pdev could exist at a time this can't
be solved with locking.

Fix that by ditching the pdev pointer and use a bus walk to reach
struct pci_dev (only one instance of a pdev can be registered at the bus
at a time).

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/arch/s390/pci/pci_debug.c b/arch/s390/pci/pci_debug.c
index 4129b0a5fd78..c555de3d12d6 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -128,10 +128,9 @@ static const struct file_operations debugfs_pci_perf_fops = {
 	.release = single_release,
 };
 
-void zpci_debug_init_device(struct zpci_dev *zdev)
+void zpci_debug_init_device(struct zpci_dev *zdev, const char *name)
 {
-	zdev->debugfs_dev = debugfs_create_dir(dev_name(&zdev->pdev->dev),
-					       debugfs_root);
+	zdev->debugfs_dev = debugfs_create_dir(name, debugfs_root);
 	if (IS_ERR(zdev->debugfs_dev))
 		zdev->debugfs_dev = NULL;