diff mbox series

[RFC,2/8] pci: make pci_destroy_dev concurrent safe

Message ID 20240722151936.1452299-3-kbusch@meta.com (mailing list archive)
State RFC
Delegated to: Bjorn Helgaas
Headers show
Series pci: rescan/remove locking rework | expand

Commit Message

Keith Busch July 22, 2024, 3:19 p.m. UTC 
From: Keith Busch <kbusch@kernel.org>

Use an atomic flag instead of the racey check against the device's kobj
parent. We shouldn't be poking into device implementation details at
this level anyway.

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
 drivers/pci/pci.h    | 6 ++++++
 drivers/pci/remove.c | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

Comments

Jonathan Cameron Aug. 15, 2024, 2:18 p.m. UTC | #1 
On Mon, 22 Jul 2024 08:19:30 -0700
Keith Busch <kbusch@meta.com> wrote:

> From: Keith Busch <kbusch@kernel.org>
> 
> Use an atomic flag instead of the racey check against the device's kobj
> parent. We shouldn't be poking into device implementation details at
> this level anyway.
> 
> Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Absolutely agree we shouldn't be poking the kobj parent here.
diff mbox series

Patch

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 171dfd6f14e6e..19cbf18743a96 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -443,6 +443,7 @@  static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused)
 #define PCI_DEV_ADDED 0
 #define PCI_DPC_RECOVERED 1
 #define PCI_DPC_RECOVERING 2
+#define PCI_DEV_REMOVED 3
 
 static inline void pci_dev_assign_added(struct pci_dev *dev)
 {
@@ -459,6 +460,11 @@  static inline bool pci_dev_is_added(const struct pci_dev *dev)
 	return test_bit(PCI_DEV_ADDED, &dev->priv_flags);
 }
 
+static inline bool pci_dev_test_and_set_removed(struct pci_dev *dev)
+{
+	return test_and_set_bit(PCI_DEV_REMOVED, &dev->priv_flags);
+}
+
 #ifdef CONFIG_PCIEAER
 #include <linux/aer.h>
 
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index ec3064a115bf8..8284ab20949c9 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -29,7 +29,7 @@  static void pci_stop_dev(struct pci_dev *dev)
 
 static void pci_destroy_dev(struct pci_dev *dev)
 {
-	if (!dev->dev.kobj.parent)
+	if (pci_dev_test_and_set_removed(dev))
 		return;
 
 	device_del(&dev->dev);