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path: root/drivers/pci
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2018-07-23PCI: pciehp: Drop enable/disable lockLukas Wunner
Previously slot enablement and disablement could happen concurrently. But now it's under the exclusive control of the IRQ thread, rendering the locking obsolete. Drop it. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Enable/disable exclusively from IRQ threadLukas Wunner
Besides the IRQ thread, there are several other places in the driver which enable or disable the slot: - pciehp_probe() enables the slot if it's occupied and the pciehp_force module parameter is used. - pciehp_resume() enables or disables the slot after system sleep. - pciehp_queue_pushbutton_work() enables or disables the slot after the 5 second delay following an Attention Button press. - pciehp_sysfs_enable_slot() and pciehp_sysfs_disable_slot() enable or disable the slot on sysfs write. This requires locking and complicates pciehp's state machine. A simplification can be achieved by enabling and disabling the slot exclusively from the IRQ thread. Amend the functions listed above to request slot enable/disablement from the IRQ thread by either synthesizing a Presence Detect Changed event or, in the case of a disable user request (via sysfs or an Attention Button press), submitting a newly introduced force disable request. The latter is needed because the slot shall be forced off despite being occupied. For this force disable request, avoid colliding with Slot Status register bits by using a bit number greater than 16. For synchronous execution of requests (on sysfs write), wait for the request to finish and retrieve the result. There can only ever be one sysfs write in flight due to the locking in kernfs_fop_write(), hence there is no risk of returning the result of a different sysfs request to user space. The POWERON_STATE and POWEROFF_STATE is now no longer entered by the above-listed functions, but solely by the IRQ thread when it begins a power transition. Afterwards, it moves to STATIC_STATE. The same applies to canceling the Attention Button work, it likewise becomes an IRQ thread only operation. An immediate consequence is that the POWERON_STATE and POWEROFF_STATE is never observed by the IRQ thread itself, only by functions called in a different context, such as pciehp_sysfs_enable_slot(). So remove handling of these states from pciehp_handle_button_press() and pciehp_handle_link_change() which are exclusively called from the IRQ thread. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Track enable/disable statusLukas Wunner
handle_button_press_event() currently determines whether the slot has been turned on or off by looking at the Power Controller Control bit in the Slot Control register. This assumes that an attention button implies presence of a power controller even though that's not mandated by the spec. Moreover the Power Controller Control bit is unreliable when a power fault occurs (PCIe r4.0, sec 6.7.1.8). This issue has existed since the driver was introduced in 2004. Fix by replacing STATIC_STATE with ON_STATE and OFF_STATE and tracking whether the slot has been turned on or off. This is also a required ingredient to make pciehp resilient to missed events, which is the object of an upcoming commit. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Publish to user space last on probeLukas Wunner
The PCI hotplug core has just been refactored to separate slot initialization for in-kernel use from publication to user space. Take advantage of it in pciehp by publishing to user space last on probe. This will allow enable/disablement of the slot exclusively from the IRQ thread because the IRQ is requested after initialization for in-kernel use (thereby getting its unique name needed by the IRQ thread) but before user space is able to submit enable/disable requests. On teardown, the order is the same in reverse: The user space interface is removed prior to freeing the IRQ and destroying the slot. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: hotplug: Demidlayer registration with the coreLukas Wunner
When a hotplug driver calls pci_hp_register(), all steps necessary for registration are carried out in one go, including creation of a kobject and addition to sysfs. That's a problem for pciehp once it's converted to enable/disable the slot exclusively from the IRQ thread: The thread needs to be spawned after creation of the kobject (because it uses the kobject's name), but before addition to sysfs (because it will handle enable/disable requests submitted via sysfs). pci_hp_deregister() does offer a ->release callback that's invoked after deletion from sysfs and before destruction of the kobject. But because pci_hp_register() doesn't offer a counterpart, hotplug drivers' ->probe and ->remove code becomes asymmetric, which is error prone as recently discovered use-after-free bugs in pciehp's ->remove hook have shown. In a sense, this appears to be a case of the midlayer antipattern: "The core thesis of the "midlayer mistake" is that midlayers are bad and should not exist. That common functionality which it is so tempting to put in a midlayer should instead be provided as library routines which can [be] used, augmented, or ignored by each bottom level driver independently. Thus every subsystem that supports multiple implementations (or drivers) should provide a very thin top layer which calls directly into the bottom layer drivers, and a rich library of support code that eases the implementation of those drivers. This library is available to, but not forced upon, those drivers." -- Neil Brown (2009), https://lwn.net/Articles/336262/ The presence of midlayer traits in the PCI hotplug core might be ascribed to its age: When it was introduced in February 2002, the blessings of a library approach might not have been well known: https://git.kernel.org/tglx/history/c/a8a2069f432c For comparison, the driver core does offer split functions for creating a kobject (device_initialize()) and addition to sysfs (device_add()) as an alternative to carrying out everything at once (device_register()). This was introduced in October 2002: https://git.kernel.org/tglx/history/c/8b290eb19962 The odd ->release callback in the PCI hotplug core was added in 2003: https://git.kernel.org/tglx/history/c/69f8d663b595 Clearly, a library approach would not force every hotplug driver to implement a ->release callback, but rather allow the driver to remove the sysfs files, release its data structures and finally destroy the kobject. Alternatively, a driver may choose to remove everything with pci_hp_deregister(), then release its data structures. To this end, offer drivers pci_hp_initialize() and pci_hp_add() as a split-up version of pci_hp_register(). Likewise, offer pci_hp_del() and pci_hp_destroy() as a split-up version of pci_hp_deregister(). Eliminate the ->release callback and move its code into each driver's teardown routine. Declare pci_hp_deregister() void, in keeping with the usual kernel pattern that enablement can fail, but disablement cannot. It only returned an error if the caller passed in a NULL pointer or a slot which has never or is no longer registered or is sharing its name with another slot. Those would be bugs, so WARN about them. Few hotplug drivers actually checked the return value and those that did only printed a useless error message to dmesg. Remove that. For most drivers the conversion was straightforward since it doesn't matter whether the code in the ->release callback is executed before or after destruction of the kobject. But in the case of ibmphp, it was unclear to me whether setting slot_cur->ctrl and slot_cur->bus_on to NULL needs to happen before the kobject is destroyed, so I erred on the side of caution and ensured that the order stays the same. Another nontrivial case is pnv_php, I've found the list and kref logic difficult to understand, however my impression was that it is safe to delete the list element and drop the references until after the kobject is destroyed. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86 Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Scott Murray <scott@spiteful.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Gavin Shan <gwshan@linux.vnet.ibm.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Corentin Chary <corentin.chary@gmail.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Andy Shevchenko <andy@infradead.org>
2018-07-23PCI: pciehp: Drop slot workqueueLukas Wunner
Previously the slot workqueue was used to handle events and enable or disable the slot. That's no longer the case as those tasks are done synchronously in the IRQ thread. The slot workqueue is thus merely used to handle a button press after the 5 second delay and only one such work item may be in flight at any given time. A separate workqueue isn't necessary for this simple task, so use the system workqueue instead. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Handle events synchronouslyLukas Wunner
Up until now, pciehp's IRQ handler schedules a work item for each event, which in turn schedules a work item to enable or disable the slot. This double indirection was necessary because sleeping wasn't allowed in the IRQ handler. However it is now that pciehp has been converted to threaded IRQ handling and polling, so handle events synchronously in pciehp_ist() and remove the work item infrastructure (with the exception of work items to handle a button press after the 5 second delay). For link or presence change events, move the register read to determine the current link or presence state behind acquisition of the slot lock to prevent it from becoming stale while the lock is contended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Stop blinking on slot enable failureLukas Wunner
If the attention button is pressed to power on the slot AND the user powers on the slot via sysfs before 5 seconds have elapsed AND powering on the slot fails because either the slot is unoccupied OR the latch is open, we neglect turning off the green LED so it keeps on blinking. That's because the error path of pciehp_sysfs_enable_slot() doesn't call pciehp_green_led_off(), unlike pciehp_power_thread() which does. The bug has been present since 2004 when the driver was introduced. Fix by deduplicating common code in pciehp_sysfs_enable_slot() and pciehp_power_thread() into a wrapper function pciehp_enable_slot() and renaming the existing function to __pciehp_enable_slot(). Same for pciehp_disable_slot(). This will also simplify the upcoming rework of pciehp's event handling. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Convert to threaded pollingLukas Wunner
We've just converted pciehp to threaded IRQ handling, but still cannot sleep in pciehp_ist() because the function is also called in poll mode, which runs in softirq context (from a timer). Convert poll mode to a kthread so that pciehp_ist() always runs in task context. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Gleixner <tglx@linutronix.de>
2018-07-23PCI: pciehp: Convert to threaded IRQLukas Wunner
pciehp's IRQ handler queues up a work item for each event signaled by the hardware. A more modern alternative is to let a long running kthread service the events. The IRQ handler's sole job is then to check whether the IRQ originated from the device in question, acknowledge its receipt to the hardware to quiesce the interrupt and wake up the kthread. One benefit is reduced latency to handle the IRQ, which is a necessity for realtime environments. Another benefit is that we can make pciehp simpler and more robust by handling events synchronously in process context, rather than asynchronously by queueing up work items. pciehp's usage of work items is a historic artifact, it predates the introduction of threaded IRQ handlers by two years. (The former was introduced in 2007 with commit 5d386e1ac402 ("pciehp: Event handling rework"), the latter in 2009 with commit 3aa551c9b4c4 ("genirq: add threaded interrupt handler support").) Convert pciehp to threaded IRQ handling by retrieving the pending events in pciehp_isr(), saving them for later consumption by the thread handler pciehp_ist() and clearing them in the Slot Status register. By clearing the Slot Status (and thereby acknowledging the events) in pciehp_isr(), we can avoid requesting the IRQ with IRQF_ONESHOT, which would have the unpleasant side effect of starving devices sharing the IRQ until pciehp_ist() has finished. pciehp_isr() does not count how many times each event occurred, but merely records the fact *that* an event occurred. If the same event occurs a second time before pciehp_ist() is woken, that second event will not be recorded separately, which is problematic according to commit fad214b0aa72 ("PCI: pciehp: Process all hotplug events before looking for new ones") because we may miss removal of a card in-between two back-to-back insertions. We're about to make pciehp_ist() resilient to missed events. The present commit regresses the driver's behavior temporarily in order to separate the changes into reviewable chunks. This doesn't affect regular slow-motion hotplug, only plug-unplug-plug operations that happen in a timespan shorter than wakeup of the IRQ thread. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mayurkumar Patel <mayurkumar.patel@intel.com> Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2018-07-23PCI: pciehp: Document struct slot and struct controllerLukas Wunner
Document the driver's data structures to lower the barrier to entry for contributors. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Declare pciehp_unconfigure_device() voidLukas Wunner
Since commit 0f4bd8014db5 ("PCI: hotplug: Drop checking of PCI_BRIDGE_ CONTROL in *_unconfigure_device()"), pciehp_unconfigure_device() can no longer fail, so declare it and its sole caller remove_board() void, in keeping with the usual kernel pattern that enablement can fail, but disablement cannot. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2018-07-23PCI: pciehp: Drop unnecessary NULL pointer checkLukas Wunner
pciehp_disable_slot() checks if the ctrl attribute of the slot is NULL and bails out if so. However the function is not called prior to the attribute being set in pcie_init_slot(), and pcie_init_slot() is not called if ctrl is NULL. So the check is unnecessary. Drop it. It has been present ever since the driver was introduced in 2004, but it was already unnecessary back then: https://git.kernel.org/tglx/history/c/c16b4b14d980 Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Fix unprotected list iteration in IRQ handlerLukas Wunner
Commit b440bde74f04 ("PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device") iterates over the devices on a hotplug port's subordinate bus in pciehp's IRQ handler without acquiring pci_bus_sem. It is thus possible for a user to cause a crash by concurrently manipulating the device list, e.g. by disabling slot power via sysfs on a different CPU or by initiating a remove/rescan via sysfs. This can't be fixed by acquiring pci_bus_sem because it may sleep. The simplest fix is to avoid the list iteration altogether and just check the ignore_hotplug flag on the port itself. This works because pci_ignore_hotplug() sets the flag both on the device as well as on its parent bridge. We do lose the ability to print the name of the device blocking hotplug in the debug message, but that's probably bearable. Fixes: b440bde74f04 ("PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device") Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org
2018-07-23PCI: pciehp: Fix use-after-free on unplugLukas Wunner
When pciehp is unbound (e.g. on unplug of a Thunderbolt device), the hotplug_slot struct is deregistered and thus freed before freeing the IRQ. The IRQ handler and the work items it schedules print the slot name referenced from the freed structure in various informational and debug log messages, each time resulting in a quadruple dereference of freed pointers (hotplug_slot -> pci_slot -> kobject -> name). At best the slot name is logged as "(null)", at worst kernel memory is exposed in logs or the driver crashes: pciehp 0000:10:00.0:pcie204: Slot((null)): Card not present An attacker may provoke the bug by unplugging multiple devices on a Thunderbolt daisy chain at once. Unplugging can also be simulated by powering down slots via sysfs. The bug is particularly easy to trigger in poll mode. It has been present since the driver's introduction in 2004: https://git.kernel.org/tglx/history/c/c16b4b14d980 Fix by rearranging teardown such that the IRQ is freed first. Run the work items queued by the IRQ handler to completion before freeing the hotplug_slot struct by draining the work queue from the ->release_slot callback which is invoked by pci_hp_deregister(). Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org # v2.6.4
2018-07-23PCI: hotplug: Don't leak pci_slot on registration failureLukas Wunner
If addition of sysfs files fails on registration of a hotplug slot, the struct pci_slot as well as the entry in the slot_list is leaked. The issue has been present since the hotplug core was introduced in 2002: https://git.kernel.org/tglx/history/c/a8a2069f432c Perhaps the idea was that even though sysfs addition fails, the slot should still be usable. But that's not how drivers use the interface, they abort probe if a non-zero value is returned. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org # v2.4.15+ Cc: Greg Kroah-Hartman <greg@kroah.com>
2018-07-23PCI: hotplug: Delete skeleton driverLukas Wunner
Ten years ago, commit 58319b802a61 ("PCI: Hotplug core: remove 'name'") dropped the name element from struct hotplug_slot but neglected to update the skeleton driver. That same year, commit f46753c5e354 ("PCI: introduce pci_slot") raised the number of arguments to pci_hp_register() from one to four. Fourteen years ago, historic commit 7ab60fc1b8e7 ("PCI Hotplug skeleton: final cleanups") removed all usages of the retval variable from pcihp_skel_init() but not the variable itself, provoking a compiler warning: https://git.kernel.org/tglx/history/c/7ab60fc1b8e7 It seems fair to assume the driver hasn't been used as a template for a new driver in a while. Per Bjorn's and Christoph's preference, delete it. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Christoph Hellwig <hch@lst.de>
2018-07-20PCI/portdrv: Remove pcie_portdrv_err_handler.slot_resetOza Pawandeep
The pci_error_handlers.slot_reset() callback is only used for non-bridge devices (see broadcast_error_message()). Since portdrv only binds to bridges, we don't need pcie_portdrv_slot_reset(), so remove it. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> [bhelgaas: changelog, remove pcie_portdrv_slot_reset() completely] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Clear device status bits during ERR_COR handlingOza Pawandeep
In case of correctable error, the Correctable Error Detected bit in the Device Status register is set. Clear it after handling the error. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Clear device status bits during ERR_FATAL and ERR_NONFATALOza Pawandeep
Clear the device status bits while handling both ERR_FATAL and ERR_NONFATAL cases. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> [bhelgaas: rename to pci_aer_clear_device_status(), declare internal to PCI core instead of exposing it everywhere] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Remove ERR_FATAL code from ERR_NONFATAL pathOza Pawandeep
broadcast_error_message() is only used for ERR_NONFATAL events, when the state is always pci_channel_io_normal, so remove the unused alternate path. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Factor out ERR_NONFATAL status bit clearingOza Pawandeep
aer_error_resume() clears all ERR_NONFATAL error status bits. This is exactly what pci_cleanup_aer_uncorrect_error_status(), so use that instead of duplicating the code. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> [bhelgaas: split to separate patch] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Clear only ERR_NONFATAL bits during non-fatal recoveryOza Pawandeep
pci_cleanup_aer_uncorrect_error_status() is called by driver .slot_reset() methods when handling ERR_NONFATAL errors. Previously this cleared *all* the bits, including ERR_FATAL bits. Since we're only handling ERR_NONFATAL errors, clear only the ERR_NONFATAL error status bits. Signed-off-by: Oza Pawandeep <poza@codeaurora.org> [bhelgaas: split to separate patch] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-20PCI/AER: Clear only ERR_FATAL status bits during fatal recoveryBjorn Helgaas
During recovery from fatal errors, we previously called pci_cleanup_aer_uncorrect_error_status(), which cleared *all* uncorrectable error status bits (both ERR_FATAL and ERR_NONFATAL). Instead, call a new pci_aer_clear_fatal_status() that clears only the ERR_FATAL bits (as indicated by the PCI_ERR_UNCOR_SEVER register). Based-on-patch-by: Oza Pawandeep <poza@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Rename pci_try_reset_bus() to pci_reset_bus()Sinan Kaya
Now that the old implementation of pci_reset_bus() is gone, replace pci_try_reset_bus() with pci_reset_bus(). Compared to the old implementation, new code will fail immmediately with -EAGAIN if object lock cannot be obtained. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Deprecate pci_reset_bus() and pci_reset_slot() functionsSinan Kaya
pci_reset_bus() and pci_reset_slot() functions are not being used by any code. Remove them from the kernel in favor of pci_try_reset_bus() and pci_try_reset_slot() functions. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Unify try slot and bus reset APISinan Kaya
Drivers are expected to call pci_try_reset_slot() or pci_try_reset_bus() by querying if a system supports hotplug or not. A survey showed that most drivers don't do this and we are leaking hotplug capability to the user. Hide pci_try_slot_reset() from drivers and embed into pci_try_bus_reset(). Change pci_try_reset_bus() parameter from struct pci_bus to struct pci_dev. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Hide pci_reset_bridge_secondary_bus() from driversSinan Kaya
Rename pci_reset_bridge_secondary_bus() to pci_bridge_secondary_bus_reset() and move the declaration from linux/pci.h to drivers/pci.h to be used internally in PCI directory only. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI: Handle error return from pci_reset_bridge_secondary_bus()Sinan Kaya
Commit 01fd61c0b9bd ("PCI: Add a return type for pci_reset_bridge_secondary_bus()") added a return value to the function to return if a device is accessible following a reset. Callers are not checking the value. Pass error code up high in the stack if device is not accessible. Fixes: 01fd61c0b9bd ("PCI: Add a return type for pci_reset_bridge_secondary_bus()") Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/IOV: Tidy pci_sriov_set_totalvfs()Bjorn Helgaas
Fix minor style issues in pci_sriov_set_totalvfs(). No functional change intended. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/DPC: Remove indirection waiting for inactive linkKeith Busch
Simplify waiting for the contained link to become inactive, removing the indirection to a unnecessary DPC-specific handler. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/DPC: Use threaded IRQ for bottom half handlingKeith Busch
Remove the work struct that was being used to handle a DPC event and use a threaded IRQ instead. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/DPC: Print AER status in DPC event handlingKeith Busch
A DPC enabled device suppresses ERR_(NON)FATAL messages, preventing the AER handler from reporting error details. If the DPC trigger reason says the downstream port detected the error, collect the AER uncorrectable status for logging, then clear the status. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/DPC: Remove rp_pio_status from dpc structKeith Busch
We don't need to save the rp pio status across multiple contexts as all DPC event handling occurs in a single work queue context. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/DPC: Defer event handling to work queueKeith Busch
Move all event handling to the existing work queue, which will make it simpler to pass event information to the handler. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/DPC: Leave interrupts enabled while handling eventKeith Busch
Now that the DPC driver clears the interrupt status before exiting the IRQ handler, we don't need to abuse the DPC control register to know if a shared interrupt is for a new DPC event: a DPC port can not trigger a second interrupt until the host clears the trigger status later in the work queue handler. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/AER: Honor "pcie_ports=native" even if HEST sets FIRMWARE_FIRSTAlexandru Gagniuc
According to the documentation, "pcie_ports=native", linux should use native AER and DPC services. While that is true for the _OSC method parsing, this is not the only place that is checked. Should the HEST list PCIe ports as firmware-first, linux will not use native services. This happens because aer_acpi_firmware_first() doesn't take 'pcie_ports' into account. This is wrong. DPC uses the same logic when it decides whether to load or not, so fixing this also fixes DPC not loading. Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> [bhelgaas: return "false" from bool function (from kbuild robot)] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/AER: Add sysfs attributes for rootport cumulative statsRajat Jain
Add sysfs attributes for rootport statistics (that are cumulative of all the ERR_* messages seen on this PCI hierarchy). Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/AER: Add sysfs attributes to provide AER stats and breakdownRajat Jain
Add sysfs attributes to provide total and breakdown of the AERs seen, into different type of correctable, fatal and nonfatal errors: /sys/bus/pci/devices/<dev>/aer_dev_correctable /sys/bus/pci/devices/<dev>/aer_dev_fatal /sys/bus/pci/devices/<dev>/aer_dev_nonfatal Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/AER: Define aer_stats structure for AER capable devicesRajat Jain
Define a structure to hold the AER statistics. There are 2 groups of statistics: dev_* counters that are to be collected for all AER capable devices and rootport_* counters that are collected for all (AER capable) rootports only. Allocate and free this structure when device is added or released (thus counters survive the lifetime of the device). Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/AER: Move internal declarations to drivers/pci/pci.hRajat Jain
Since pci_aer_init() and pci_no_aer() are used only internally, move their declarations to the PCI internal header file. Also, no one cares about return value of pci_aer_init(), so make it void. Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19PCI/AER: Adopt lspci names for AER error decodingTyler Baicar
lspci uses abbreviated naming for AER error strings. Adopt the same naming convention for the AER printing so they match. Signed-off-by: Tyler Baicar <tbaicar@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19PCI/AER: Expose internal API for obtaining AER informationKeith Busch
Export some common AER functions and structures for other PCI core drivers to use. Since this is making the function externally visible inside the PCI core, prepend "aer_" to the function name. Signed-off-by: Keith Busch <keith.busch@intel.com> [bhelgaas: move AER declarations from linux/aer.h to drivers/pci/pci.h] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org> Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
2018-07-19Merge tag 'pci-v4.18-fixes-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI fixes from Bjorn Helgaas: - Fix crashes that happen when PHY drivers are left disabled in the V3 Semiconductor, MediaTek, Faraday, Aardvark, DesignWare, Versatile, and X-Gene host controller drivers (Sergei Shtylyov) - Fix a NULL pointer dereference in the endpoint library configfs support (Kishon Vijay Abraham I) - Fix a race condition in Hyper-V IRQ handling (Dexuan Cui) * tag 'pci-v4.18-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI: v3-semi: Fix I/O space page leak PCI: mediatek: Fix I/O space page leak PCI: faraday: Fix I/O space page leak PCI: aardvark: Fix I/O space page leak PCI: designware: Fix I/O space page leak PCI: versatile: Fix I/O space page leak PCI: xgene: Fix I/O space page leak PCI: OF: Fix I/O space page leak PCI: endpoint: Fix NULL pointer dereference error when CONFIGFS is disabled PCI: hv: Disable/enable IRQs rather than BH in hv_compose_msi_msg()
2018-07-19PCI: endpoint: Add MSI set maximum restrictionGustavo Pimentel
Add pci_epc_set_msi() maximum 32 interrupts validation. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-07-19pci-epf-test/pci_endpoint_test: Add MSI-X supportGustavo Pimentel
Add MSI-X support and update driver documentation accordingly. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-07-19pci-epf-test/pci_endpoint_test: Cleanup PCI_ENDPOINT_TEST memspaceGustavo Pimentel
Cleanup PCI_ENDPOINT_TEST memspace (by moving the interrupt number away from command section). Add IRQ_TYPE register to identify the triggered ID interrupt required for the READ/WRITE/COPY tests and raise IRQ test commands. Update documentation accordingly. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-07-19PCI: dwc: Add legacy interrupt callback handlerGustavo Pimentel
Currently DesignWare IP does not handle legacy interrupts. Add a legacy interrupt callback handler. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-07-19PCI: dwc: Rework MSI callbacks handlerGustavo Pimentel
Remove duplicate defines located on pcie-designware.h file already available on /include/uapi/linux/pci-regs.h file. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2018-07-19PCI: dwc: Add MSI-X callbacks handlerGustavo Pimentel
Add PCIe config space capability search function. Add sysfs set/get interface to allow the change of EP MSI-X maximum number. Add EP MSI-X callback for triggering interruptions. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>