On 8/12/2024 15:51, Bjorn Helgaas wrote:
[+cc Mario, 7d08f21f8c63 author]
On Mon, Aug 12, 2024 at 01:26:59PM -0700, Samasth Norway Ananda wrote:
If pcie_find_root_port() is unable to locate a root port, it will return
NULL. This NULL pointer needs to be handled before trying to dereference.
Fixes: 7d08f21f8c63 ("x86/PCI: Avoid PME from D3hot/D3cold for AMD Rembrandt and Phoenix USB4")
Signed-off-by: Samasth Norway Ananda <samasth.norway.ananda@xxxxxxxxxx>
---
arch/x86/pci/fixup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index b33afb240601..98a9bb92d75c 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -980,7 +980,7 @@ static void amd_rp_pme_suspend(struct pci_dev *dev)
return;
rp = pcie_find_root_port(dev);
- if (!rp->pm_cap)
+ if (!rp || !rp->pm_cap)
Seems reasonable. I suspect we haven't seen problems because these
quirks are limited to Device IDs that are all PCIe, but I think we
should check on principle and because it may be copied elsewhere where
it *does* matter.
Yeah totally agree, if nothing else it prevents copy/paste mistakes.
HOWEVER I don't think this needs to be a "Fixes" tag because there is no
problem in THIS code on the applicable systems. Those PCI devices are
always attached to a root port. So Bjorn I would suggest stripping the
Fixes tag when committing.
Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
return;
rp->pme_support &= ~((PCI_PM_CAP_PME_D3hot|PCI_PM_CAP_PME_D3cold) >>
@@ -994,7 +994,7 @@ static void amd_rp_pme_resume(struct pci_dev *dev)
u16 pmc;
rp = pcie_find_root_port(dev);
- if (!rp->pm_cap)
+ if (!rp || !rp->pm_cap)
return;
pci_read_config_word(rp, rp->pm_cap + PCI_PM_PMC, &pmc);
--
2.45.2
