kernel.git/drivers/pci/pcie, branch linux-3.2.y

PCI/AER: Report non-fatal errors only to the affected endpoint

2018-02-13T18:32:08Z

commit 86acc790717fb60fb51ea3095084e331d8711c74 upstream. Previously, if an non-fatal error was reported by an endpoint, we called report_error_detected() for the endpoint, every sibling on the bus, and their descendents. If any of them did not implement the .error_detected() method, do_recovery() failed, leaving all these devices unrecovered. For example, the system described in the bugzilla below has two devices: 0000:74:02.0 [19e5:a230] SAS controller, driver has .error_detected() 0000:74:03.0 [19e5:a235] SATA controller, driver lacks .error_detected() When a device such as 74:02.0 reported a non-fatal error, do_recovery() failed because 74:03.0 lacked an .error_detected() method. But per PCIe r3.1, sec 6.2.2.2.2, such an error does not compromise the Link and does not affect 74:03.0: Non-fatal errors are uncorrectable errors which cause a particular transaction to be unreliable but the Link is otherwise fully functional. Isolating Non-fatal from Fatal errors provides Requester/Receiver logic in a device or system management software the opportunity to recover from the error without resetting the components on the Link and disturbing other transactions in progress. Devices not associated with the transaction in error are not impacted by the error. Report non-fatal errors only to the endpoint that reported them. We really want to check for AER_NONFATAL here, but the current code structure doesn't allow that. Looking for pci_channel_io_normal is the best we can do now. Link: https://bugzilla.kernel.org/show_bug.cgi?id=197055 Fixes: 6c2b374d7485 ("PCI-Express AER implemetation: AER core and aerdriver") Signed-off-by: Gabriele Paoloni Signed-off-by: Dongdong Liu [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI/AER: Flush workqueue on device remove to avoid use-after-free

2016-02-27T14:28:43Z

commit 4ae2182b1e3407de369f8c5d799543b7db74221b upstream. A Root Port's AER structure (rpc) contains a queue of events. aer_irq() enqueues AER status information and schedules aer_isr() to dequeue and process it. When we remove a device, aer_remove() waits for the queue to be empty, then frees the rpc struct. But aer_isr() references the rpc struct after dequeueing and possibly emptying the queue, which can cause a use-after-free error as in the following scenario with two threads, aer_isr() on the left and a concurrent aer_remove() on the right: Thread A Thread B -------- -------- aer_irq(): rpc->prod_idx++ aer_remove(): wait_event(rpc->prod_idx == rpc->cons_idx) # now blocked until queue becomes empty aer_isr(): # ... rpc->cons_idx++ # unblocked because queue is now empty ... kfree(rpc) mutex_unlock(&rpc->rpc_mutex) To prevent this problem, use flush_work() to wait until the last scheduled instance of aer_isr() has completed before freeing the rpc struct in aer_remove(). I reproduced this use-after-free by flashing a device FPGA and re-enumerating the bus to find the new device. With SLUB debug, this crashes with 0x6b bytes (POISON_FREE, the use-after-free magic number) in GPR25: pcieport 0000:00:00.0: AER: Multiple Corrected error received: id=0000 Unable to handle kernel paging request for data at address 0x27ef9e3e Workqueue: events aer_isr GPR24: dd6aa000 6b6b6b6b 605f8378 605f8360 d99b12c0 604fc674 606b1704 d99b12c0 NIP [602f5328] pci_walk_bus+0xd4/0x104 [bhelgaas: changelog, stable tag] Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI: Remove duplicate pci_disable_device() from pcie_portdrv_remove()

2014-01-03T04:33:23Z

commit e7cc5cf74544d97d7b69e2701595037474db1f96 upstream. The pcie_portdrv .probe() method calls pci_enable_device() once, in pcie_port_device_register(), but the .remove() method calls pci_disable_device() twice, in pcie_port_device_remove() and in pcie_portdrv_remove(). That causes a "disabling already-disabled device" warning when removing a PCIe port device. This happens all the time when removing Thunderbolt devices, but is also easy to reproduce with, e.g., "echo 0000:00:1c.3 > /sys/bus/pci/drivers/pcieport/unbind" This patch removes the disable from pcie_portdrv_remove(). [bhelgaas: changelog, tag for stable] Reported-by: David Bulkow Reported-by: Mika Westerberg Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI: Allow pcie_aspm=force even when FADT indicates it is unsupported

2013-02-06T04:33:34Z

commit 9e16721498b0c3d3ebfa0b503c63d35c0a4c0642 upstream. Right now using pcie_aspm=force will not enable ASPM if the FADT indicates ASPM is unsupported. However, the semantics of force should probably allow for this, especially as they did before 3c076351c4 ("PCI: Rework ASPM disable code") This patch just skips the clearing of any ASPM setup that the firmware has carried out on this bus if pcie_aspm=force is being used. Reference: http://bugs.launchpad.net/bugs/962038 Signed-off-by: Colin Ian King Signed-off-by: Bjorn Helgaas Signed-off-by: Ben Hutchings

PCI/AER: pci_get_domain_bus_and_slot() call missing required pci_dev_put()

2013-02-06T04:33:33Z

commit a82b6af37d20bfe6e99a4d890f1cf1d89059929f upstream. The function aer_recover_queue() calls pci_get_domain_bus_and_slot(), which requires that the caller decrement the reference count with pci_dev_put(). This patch adds the missing call to pci_dev_put(). Signed-off-by: Betty Dall Signed-off-by: Bjorn Helgaas Reviewed-by: Shuah Khan Signed-off-by: Ben Hutchings

ASPM: Fix pcie devices with non-pcie children

2012-04-02T16:53:10Z

commit c9651e70ad0aa499814817cbf3cc1d0b806ed3a1 upstream. Since 3.2.12 and 3.3, some systems are failing to boot with a BUG_ON. Some other systems using the pata_jmicron driver fail to boot because no disks are detected. Passing pcie_aspm=force on the kernel command line works around it. The cause: commit 4949be16822e ("PCI: ignore pre-1.1 ASPM quirking when ASPM is disabled") changed the behaviour of pcie_aspm_sanity_check() to always return 0 if aspm is disabled, in order to avoid cases where we changed ASPM state on pre-PCIe 1.1 devices. This skipped the secondary function of pcie_aspm_sanity_check which was to avoid us enabling ASPM on devices that had non-PCIe children, causing trouble later on. Move the aspm_disabled check so we continue to honour that scenario. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=42979 and http://bugs.debian.org/665420 Reported-by: Romain Francoise # kernel panic Reported-by: Chris Holland # disk detection trouble Signed-off-by: Matthew Garrett Tested-by: Hatem Masmoudi # Dell Latitude E5520 Tested-by: janek # pata_jmicron with JMB362/JMB363 [jn: with more symptoms in log message] Signed-off-by: Jonathan Nieder Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

PCI: ignore pre-1.1 ASPM quirking when ASPM is disabled

2012-03-19T16:02:19Z

commit 4949be16822e92a18ea0cc1616319926628092ee upstream. Right now we won't touch ASPM state if ASPM is disabled, except in the case where we find a device that appears to be too old to reliably support ASPM. Right now we'll clear it in that case, which is almost certainly the wrong thing to do. The easiest way around this is just to disable the blacklisting when ASPM is disabled. Signed-off-by: Matthew Garrett Signed-off-by: Jesse Barnes Signed-off-by: Greg Kroah-Hartman

PCI: Rework ASPM disable code

2012-02-06T17:41:06Z

commit 3c076351c4027a56d5005a39a0b518a4ba393ce2 upstream. Right now we forcibly clear ASPM state on all devices if the BIOS indicates that the feature isn't supported. Based on the Microsoft presentation "PCI Express In Depth for Windows Vista and Beyond", I'm starting to think that this may be an error. The implication is that unless the platform grants full control via _OSC, Windows will not touch any PCIe features - including ASPM. In that case clearing ASPM state would be an error unless the platform has granted us that control. This patch reworks the ASPM disabling code such that the actual clearing of state is triggered by a successful handoff of PCIe control to the OS. The general ASPM code undergoes some changes in order to ensure that the ability to clear the bits isn't overridden by ASPM having already been disabled. Further, this theoretically now allows for situations where only a subset of PCIe roots hand over control, leaving the others in the BIOS state. It's difficult to know for sure that this is the right thing to do - there's zero public documentation on the interaction between all of these components. But enough vendors enable ASPM on platforms and then set this bit that it seems likely that they're expecting the OS to leave them alone. Measured to save around 5W on an idle Thinkpad X220. Signed-off-by: Matthew Garrett Signed-off-by: Jesse Barnes Signed-off-by: Greg Kroah-Hartman

PCI / PM: Extend PME polling to all PCI devices

2011-10-14T16:05:31Z

The land of PCI power management is a land of sorrow and ugliness, especially in the area of signaling events by devices. There are devices that set their PME Status bits, but don't really bother to send a PME message or assert PME#. There are hardware vendors who don't connect PME# lines to the system core logic (they know who they are). There are PCI Express Root Ports that don't bother to trigger interrupts when they receive PME messages from the devices below. There are ACPI BIOSes that forget to provide _PRW methods for devices capable of signaling wakeup. Finally, there are BIOSes that do provide _PRW methods for such devices, but then don't bother to call Notify() for those devices from the corresponding _Lxx/_Exx GPE-handling methods. In all of these cases the kernel doesn't have a chance to receive a proper notification that it should wake up a device, so devices stay in low-power states forever. Worse yet, in some cases they continuously send PME Messages that are silently ignored, because the kernel simply doesn't know that it should clear the device's PME Status bit. This problem was first observed for "parallel" (non-Express) PCI devices on add-on cards and Matthew Garrett addressed it by adding code that polls PME Status bits of such devices, if they are enabled to signal PME, to the kernel. Recently, however, it has turned out that PCI Express devices are also affected by this issue and that it is not limited to add-on devices, so it seems necessary to extend the PME polling to all PCI devices, including PCI Express and planar ones. Still, it would be wasteful to poll the PME Status bits of devices that are known to receive proper PME notifications, so make the kernel (1) poll the PME Status bits of all PCI and PCIe devices enabled to signal PME and (2) disable the PME Status polling for devices for which correct PME notifications are received. Tested-by: Sarah Sharp Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes

Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6

2011-07-30T06:35:05Z

* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: PCI: remove printks about disabled bridge windows PCI: fold pci_calc_resource_flags() into decode_bar() PCI: treat mem BAR type "11" (reserved) as 32-bit, not 64-bit, BAR PCI: correct pcie_set_readrq write size PCI: pciehp: change wait time for valid configuration access x86/PCI: Preserve existing pci=bfsort whitelist for Dell systems PCI: ARI is a PCIe v2 feature x86/PCI: quirks: Use pci_dev->revision PCI: Make the struct pci_dev * argument of pci_fixup_irqs const. PCI hotplug: cpqphp: use pci_dev->vendor PCI hotplug: cpqphp: use pci_dev->subsystem_{vendor|device} x86/PCI: config space accessor functions should not ignore the segment argument PCI: Assign values to 'pci_obff_signal_type' enumeration constants x86/PCI: reduce severity of host bridge window conflict warnings PCI: enumerate the PCI device only removed out PCI hieratchy of OS when re-scanning PCI PCI: PCIe AER: add aer_recover_queue x86/PCI: select direct access mode for mmconfig option PCI hotplug: Rename is_ejectable which also exists in dock.c