PCI: fix a scheduling in atomic bug

This function is often called with a spinlock held so the allocation has to be atomic. The call tree is:

pci_specified_resource_alignment() <-- takes spin_lock();
-> pci_dev_str_match()

    -> pci_dev_str_match_path()

Fixes 07d8d7e57c28 ("PCI: Make specifying PCI devices in kernel parameters reusable")

Signed-off-by Dan Carpenter <[email protected]>

Quoted 7 lines · Dan Carpenter

This function is often called with a spinlock held so the allocation has to be atomic. The call tree is:

pci_specified_resource_alignment() <-- takes spin_lock();
-> pci_dev_str_match()

    -> pci_dev_str_match_path()

Quoted 2 lines

Fixes 07d8d7e57c28 ("PCI: Make specifying PCI devices in kernel parameters reusable")

Signed-off-by Dan Carpenter <[email protected]>

This looks good to me, but I think the fixes tag is wrong. pci_dev_str_match_path() was introduced in this patch:

Fixes 45db33709ccc ("PCI: Allow specifying devices using a base bus and

path of devfns")

This function is often called with a spinlock held so the allocation has to be atomic. The call tree is:

pci_specified_resource_alignment() <-- takes spin_lock();
-> pci_dev_str_match()

    -> pci_dev_str_match_path()

Fixes 07d8d7e57c28 ("PCI: Make specifying PCI devices in kernel parameters reusable")

Signed-off-by Dan Carpenter <[email protected]>

---
 drivers/pci/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/pci/pci.c +1 -1

index 6714c58ce321..71baf5ff48fc 100644
@@ -269,7 +269,7 @@ static int pci_dev_str_match_path(struct pci_dev *dev, const char *path,
 
 	*endptr = strchrnul(path, ';');
 
-	wpath = kmemdup_nul(path, *endptr - path, GFP_KERNEL);
+	wpath = kmemdup_nul(path, *endptr - path, GFP_ATOMIC);
 	if (!wpath)
 		return -ENOMEM;
 

Signature · 1 line

2.20.1