user/sven/linux.git/drivers/pci/hotplug, branch v3.2.65

PCI: pciehp: Prevent NULL dereference during probe

2014-12-14T16:23:42Z

commit bceee4a97eb58bd0e80e39eff11b506ddd9e7ad3 upstream. pciehp assumes that dev->subordinate, the struct pci_bus for a bridge's secondary bus, exists. But we do not create that bus if we run out of bus numbers during enumeration. This leads to a NULL dereference in init_slot() (and other places). Change pciehp_probe() to return -ENODEV when no secondary bus is present. Signed-off-by: Andreas Noever Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI: shpchp: Check bridge's secondary (not primary) bus speed

2014-06-09T12:29:12Z

commit 93fa9d32670f5592c8e56abc9928fc194e1e72fc upstream. When a new device is added below a hotplug bridge, the bridge's secondary bus speed and the device's bus speed must match. The shpchp driver previously checked the bridge's *primary* bus speed, not the secondary bus speed. This caused hot-add errors like: shpchp 0000:00:03.0: Speed of bus ff and adapter 0 mismatch Check the secondary bus speed instead. [bhelgaas: changelog] Link: https://bugzilla.kernel.org/show_bug.cgi?id=75251 Fixes: 3749c51ac6c1 ("PCI: Make current and maximum bus speeds part of the PCI core") Signed-off-by: Marcel Apfelbaum Signed-off-by: Bjorn Helgaas Acked-by: Michael S. Tsirkin Signed-off-by: Ben Hutchings

PCI: shpchp: Use per-slot workqueues to avoid deadlock

2013-02-06T04:33:33Z

commit f652e7d2916fe2fcf9e7d709aa5b7476b431e2dd upstream. When we have an SHPC-capable bridge with a second SHPC-capable bridge below it, pushing the upstream bridge's attention button causes a deadlock. The deadlock happens because we use the shpchp_wq workqueue to run shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove devices below the upstream bridge. When we remove the downstream bridge, we call shpc_remove(), the shpchp driver's .remove() method. That calls flush_workqueue(shpchp_wq), which deadlocks because the shpchp_pushbutton_thread() work item is still running. This patch avoids the deadlock by creating a workqueue for every slot and removing the single shared workqueue. Here's the call path that leads to the deadlock: shpchp_queue_pushbutton_work queue_work(shpchp_wq) # shpchp_pushbutton_thread ... shpchp_pushbutton_thread shpchp_disable_slot remove_board shpchp_unconfigure_device pci_stop_and_remove_bus_device ... shpc_remove # shpchp driver .remove method hpc_release_ctlr cleanup_slots flush_workqueue(shpchp_wq) This change is based on code inspection, since we don't have hardware with this topology. Based-on-patch-by: Yijing Wang Signed-off-by: Bjorn Helgaas [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

PCI: shpchp: Handle push button event asynchronously

2013-02-06T04:33:33Z

commit d347e75847c1fb299c97736638f45e6ea39702d4 upstream. Use non-ordered workqueue for attention button events. Attention button events on each slot can be handled asynchronously. So we should use non-ordered workqueue. This patch also removes ordered workqueue in shpchp as a result. 486b10b9f4 ("PCI: pciehp: Handle push button event asynchronously") made the same change to pciehp. I split this out from a patch by Yijing Wang so we fix one thing at a time and to make the shpchp history correspond more closely with the pciehp history. Signed-off-by: Bjorn Helgaas CC: Kenji Kaneshige Signed-off-by: Ben Hutchings

PCI: pciehp: Use per-slot workqueues to avoid deadlock

2013-02-06T04:33:32Z

commit c2be6f93b383c873a4f9d521afa49b1b67d06085 upstream. When we have a hotplug-capable PCIe port with a second hotplug-capable PCIe port below it, removing the device below the upstream port causes a deadlock. The deadlock happens because we use the pciehp_wq workqueue to run pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices below the upstream port. When we remove the downstream PCIe port, we call pciehp_remove(), the pciehp driver's .remove() method. That calls flush_workqueue(pciehp_wq), which deadlocks because the pciehp_power_thread() work item is still running. This patch avoids the deadlock by creating a workqueue for every PCIe port and removing the single shared workqueue. Here's the call path that leads to the deadlock: pciehp_queue_pushbutton_work queue_work(pciehp_wq) # queue pciehp_power_thread ... pciehp_power_thread pciehp_disable_slot remove_board pciehp_unconfigure_device pci_stop_and_remove_bus_device ... pciehp_remove # pciehp driver .remove method pciehp_release_ctrl pcie_cleanup_slot flush_workqueue(pciehp_wq) This is fairly urgent because it can be caused by simply unplugging a Thunderbolt adapter, as reported by Daniel below. [bhelgaas: changelog] Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com Reported-and-tested-by: Daniel J Blueman Reviewed-by: Kenji Kaneshige Signed-off-by: Yijing Wang Signed-off-by: Bjorn Helgaas [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

PCI: pciehp: Handle push button event asynchronously

2013-02-06T04:33:32Z

commit 486b10b9f43500741cd63a878d0ef23cd87fc66d upstream. Use non-ordered workqueue for attention button events. Attention button events on each slot can be handled asynchronously. So we should use non-ordered workqueue. This patch also removes ordered workqueue in pciehp as a result. Signed-off-by: Kenji Kaneshige Signed-off-by: Jesse Barnes Signed-off-by: Ben Hutchings

PCI: pciehp: Fix wrong workqueue cleanup

2013-02-06T04:33:32Z

commit 027e8d52abdd44bc00e405af83cd2fbfb96c0824 upstream. Fix improper workqueue cleanup. In the current pciehp, pcied_cleanup() calls destroy_workqueue() before calling pcie_port_service_unregister(). This causes kernel oops because flush_workqueue() is called in the pcie_port_service_unregister() code path after the workqueue was destroyed. So pcied_cleanup() must call pcie_port_service_unregister() first before calling destroy_workqueue(). Signed-off-by: Kenji Kaneshige Signed-off-by: Jesse Barnes Signed-off-by: Ben Hutchings

PCI: acpiphp: check whether _ADR evaluation succeeded

2012-10-10T02:31:18Z

commit dfb117b3e50c52c7b3416db4a4569224b8db80bb upstream. Check whether we evaluated _ADR successfully. Previously we ignored failure, so we would have used garbage data from the stack as the device and function number. We return AE_OK so that we ignore only this slot and continue looking for other slots. Found by Coverity (CID 113981). Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI: Set device power state to PCI_D0 for device without native PM support

2011-12-14T16:26:42Z

During test of one IB card with guest VM, found that, msi is not initialized properly. It turns out __write_msi_msg will do nothing if device current_state is not PCI_D0. And, that pci device does not have pm_cap in guest VM. There is an error in setting of power state to PCI_D0 in pci_enable_device(), but error is not returned for this. Following is code flow: pci_enable_device() --> __pci_enable_device_flags() --> do_pci_enable_device() --> pci_set_power_state() --> __pci_start_power_transition() We have following condition inside __pci_start_power_transition(): if (platform_pci_power_manageable(dev)) { error = platform_pci_set_power_state(dev, state); if (!error) pci_update_current_state(dev, state); } else { error = -ENODEV; /* Fall back to PCI_D0 if native PM is not supported */ if (!dev->pm_cap) dev->current_state = PCI_D0; } Here, from platform_pci_set_power_state(), acpi_pci_set_power_state() is getting called and that is failing with ENODEV because of following condition: if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0",&tmp))) return -ENODEV; Because of that, pci_update_current_state() is not getting called. With this patch, if device power state can not be set via platform_pci_set_power_state and that device does not have native pm support, then PCI device power state will be set to PCI_D0. -v2: This also reverts 47e9037ac16637cd7f12b8790ea7ce6680e42168, as it's not needed after this change. Acked-by: "Rafael J. Wysocki" Signed-off-by: Ajaykumar Hotchandani Signed-off-by: Yinghai Lu Signed-off-by: Jesse Barnes

PCI hotplug: Always allow acpiphp to handle non-PCIe bridges

2011-12-13T18:41:23Z

Commit 0d52f54e2ef64c189dedc332e680b2eb4a34590a (PCI / ACPI: Make acpiphp ignore root bridges using PCIe native hotplug) added code that made the acpiphp driver completely ignore PCIe root complexes for which the kernel had been granted control of the native PCIe hotplug feature by the BIOS through _OSC. Unfortunately, however, this was a mistake, because on some systems there were PCI bridges supporting PCI (non-PCIe) hotplug under such root complexes and those bridges should have been handled by acpiphp. For this reason, revert the changes made by the commit mentioned above and make register_slot() in drivers/pci/hotplug/acpiphp_glue.c avoid registering hotplug slots for PCIe ports that belong to root complexes with native PCIe hotplug enabled (which means that the BIOS has granted the kernel control of this feature for the given root complex). This is reported to address the original issue fixed by commit 0d52f54e2ef64c189dedc332e680b2eb4a34590a and to work on the system where that commit broke things. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes