Now that ASPM is configured for *all* PCIE devices at boot, a problem is seen
with systems that set the FADT NO_ASPM bit. This bit indicates that the OS
should not alter the ASPM state, but when pcie_aspm_init_link_state() runs it
only checks for !aspm_support_enabled. This misses the ACPI_FADT_NO_ASPM case
because that is setting aspm_disabled.
The result is systems may hang at boot after 1302fcf; avoidable if they boot
with pcie_aspm=off (sets !aspm_support_enabled).
Fix this by having aspm_init_link_state() check for either !aspm_support_enabled
or acpm_disabled.
Fixes: 1302fcf ("PCI: Configure *all* devices, not just hot-added ones")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201001
Signed-off-by: Patrick Talbert <ptalbert@xxxxxxxxxx>
---
drivers/pci/pcie/aspm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 53269167..4feb8ba 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -895,7 +895,7 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
struct pcie_link_state *link;
int blacklist = !!pcie_aspm_sanity_check(pdev);
- if (!aspm_support_enabled)
+ if (!aspm_support_enabled || aspm_disabled)
return;
if (pdev->link_state)
--
1.8.3.1
