Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
PCI/portdrv: Enable Bandwidth Notification only if port supports it
commit 00823dc upstream. Previously we assumed that all Root Ports and Switch Downstream Ports supported Link Bandwidth Notification. Per spec, this is only required for Ports supporting Links wider than x1 and/or multiple Link speeds (PCIe r5.0, sec 7.5.3.6). Because we assumed all Ports supported it, we tried to set up a Bandwidth Notification IRQ, which failed for devices that don't support IRQs at all, which meant pcieport didn't attach to the Port at all. Check the Link Bandwidth Notification Capability bit and enable the service only when the Port supports it. [bhelgaas: commit log] Fixes: e8303bb ("PCI/LINK: Report degraded links via link bandwidth notification") Link: https://lore.kernel.org/r/20210512213314.7778-1-stuart.w.hayes@gmail.com Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Loading branch information