[PATCH 6.18.y 3/8] PCI: Try BAR resize even when no window was released

[Sasha Levin <sashal@kernel.org>]

From: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

[ Upstream commit 121d3e9e4b217f2f23715901fb15c6a3ca2bab46 ]

Usually, resizing BARs requires releasing bridge windows in order to
resize it to fit a larger BAR into the window. This is not always the
case, however, FW could have made the window large enough to accommodate
larger BAR as is, or the user might prefer to shrink a BAR to make more
space for another Resizable BAR.

Thus, replace the check that requires that at least one bridge window
was released with a check that simply ensures bridge is not NULL.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Alex Bennée <alex.bennee@linaro.org> # AVA, AMD GPU
Link: https://patch.msgid.link/20251113162628.5946-5-ilpo.jarvinen@linux.intel.com
Stable-dep-of: ee7471fe968d ("PCI: Skip Resizable BAR restore on read error")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/setup-bus.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index ae72a34b09c562..55f3ac3f3eb1cc 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -2376,7 +2376,7 @@ int pbus_reassign_bridge_resources(struct pci_bus *bus, struct resource *res)
 {
 	unsigned long type = res->flags;
 	struct pci_dev_resource *dev_res;
-	struct pci_dev *bridge;
+	struct pci_dev *bridge = NULL;
 	LIST_HEAD(saved);
 	LIST_HEAD(added);
 	LIST_HEAD(failed);
@@ -2411,10 +2411,8 @@ int pbus_reassign_bridge_resources(struct pci_bus *bus, struct resource *res)
 		bus = bus->parent;
 	}
 
-	if (list_empty(&saved)) {
-		up_read(&pci_bus_sem);
+	if (!bridge)
 		return -ENOENT;
-	}
 
 	__pci_bus_size_bridges(bridge->subordinate, &added);
 	__pci_bridge_assign_resources(bridge, &added, &failed);
-- 
2.53.0