diff options
| author | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2020-09-04 15:09:04 +0100 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2020-09-08 16:52:42 -0500 |
| commit | e338eecf3fe79054e8a31b8c39a1234b5acfdabe (patch) | |
| tree | 155e65e0a9fa813e32535dc256fe4330e8b2b8d4 /drivers/pci | |
| parent | 7c2308f79fc81ba0bf24ccd2429fb483a91bcd51 (diff) | |
PCI: rockchip: Fix bus checks in rockchip_pcie_valid_device()
The root bus checks rework in d84c572de1a3 ("PCI: rockchip: Use
pci_is_root_bus() to check if bus is root bus") caused a regression whereby
in rockchip_pcie_valid_device() if the bus parameter is the root bus and
the dev value == 0, the function should return 1 (ie true) without checking
if the bus->parent pointer is a root bus because that triggers a NULL
pointer dereference.
Fix this by streamlining the root bus detection.
Fixes: d84c572de1a3 ("PCI: rockchip: Use pci_is_root_bus() to check if bus is root bus")
Link: https://lore.kernel.org/r/20200904140904.944-1-lorenzo.pieralisi@arm.com
Reported-by: Samuel Dionne-Riel <samuel@dionne-riel.com>
Tested-by: Samuel Dionne-Riel <samuel@dionne-riel.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/controller/pcie-rockchip-host.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/drivers/pci/controller/pcie-rockchip-host.c b/drivers/pci/controller/pcie-rockchip-host.c index 0bb2fb3e8a0b..9705059523a6 100644 --- a/drivers/pci/controller/pcie-rockchip-host.c +++ b/drivers/pci/controller/pcie-rockchip-host.c @@ -71,16 +71,13 @@ static void rockchip_pcie_update_txcredit_mui(struct rockchip_pcie *rockchip) static int rockchip_pcie_valid_device(struct rockchip_pcie *rockchip, struct pci_bus *bus, int dev) { - /* access only one slot on each root port */ - if (pci_is_root_bus(bus) && dev > 0) - return 0; - /* - * do not read more than one device on the bus directly attached + * Access only one slot on each root port. + * Do not read more than one device on the bus directly attached * to RC's downstream side. */ - if (pci_is_root_bus(bus->parent) && dev > 0) - return 0; + if (pci_is_root_bus(bus) || pci_is_root_bus(bus->parent)) + return dev == 0; return 1; } |