Hi Xiaotian, Thanks for the bug report. * Xiaotian Feng <dfeng@xxxxxxxxxx>: > commit 275582 introduces acpi_get_pci_dev(), but pdev->subordinate > can be NULL, then a NULL was passed to pci_get_slot, this results > the kernel oops when resume from suspend. > > This patch resolves following kernel oops: > BUG: unable to handle kernel NULL pointer dereference at 0000000000000028 > IP: [<ffffffff812217e7>] pci_get_slot+0x4c/0x8c > > Signed-off-by: Xiaotian Feng <dfeng@xxxxxxxxxx> > --- > drivers/acpi/pci_root.c | 6 +++++- > 1 files changed, 5 insertions(+), 1 deletions(-) > > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > index 3112221..3c35144 100644 > --- a/drivers/acpi/pci_root.c > +++ b/drivers/acpi/pci_root.c > @@ -387,7 +387,11 @@ struct pci_dev *acpi_get_pci_dev(acpi_handle handle) > if (!pdev || hnd == handle) > break; > > - pbus = pdev->subordinate; > + if (pdev->subordinate) > + pbus = pdev->subordinate; > + else > + pbus = pdev->bus; > + I'm a little confused by this. If we start from the PCI root bridge and walk back down the hierarchy, shouldn't everything between the root and the device be a P2P bridge? What is special about suspend/resume that causes the subordinate bus to become NULL? Can you send the full stacktrace? Thanks. /ac -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
