- 31 Jul, 2018 2 commits
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Lukas Wunner authored
Replace suspend_iter() and resume_iter() with a single function pm_iter() to allow addition of port service callbacks for further power management phases without having to add another iterator each time. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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Lukas Wunner authored
The ->reset_slot callback introduced by commits: 2e35afae ("PCI: pciehp: Add reset_slot() method") and 06a8d89a ("PCI: pciehp: Disable link notification across slot reset") disables notification of Presence Detect Changed and Data Link Layer State Changed events for the duration of a secondary bus reset. However a bus reset not only triggers these events, but may also clear the Presence Detect State bit in the Slot Status register and the Data Link Layer Link Active bit in the Link Status register momentarily. According to Sinan Kaya: "I know for a fact that bus reset clears the Data Link Layer Active bit as soon as link goes down. It gets set again following link up. Presence detect depends on the HW implementation. QDT root ports don't change presence detect for instance since nobody actually removed the card. If an implementation supports in-band presence detect, the answer is yes. As soon as the link goes down, presence detect bit will get cleared until recovery." https://lkml.kernel.org/r/42e72f83-3b24-f7ef-e5bc-290fae99259a@codeaurora.org In-band presence detect is also covered in Table 4-15 in PCIe r4.0, sec 4.2.6. pciehp should therefore ensure that any parts of the driver that access those bits do not run concurrently to a bus reset. The only precaution the commits took to that effect was to halt interrupt polling. They made no effort to drain the slot workqueue, cancel an outstanding Attention Button work, or block slot enable/disable requests via sysfs and in the ->probe hook. Now that pciehp is converted to enable/disable the slot exclusively from the IRQ thread, the only places accessing the two above-mentioned bits are the IRQ thread and the ->probe hook. Add locking to serialize them with a bus reset. This obviates the need to halt interrupt polling. Do not add locking to the ->get_adapter_status sysfs callback to afford users unfettered access to that bit. Use an rw_semaphore in lieu of a regular mutex to allow parallel execution of the non-reset code paths accessing the critical bits, i.e. the IRQ thread and the ->probe hook. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Rajat Jain <rajatja@google.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Sinan Kaya <okaya@kernel.org>
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- 23 Jul, 2018 21 commits
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Lukas Wunner authored
Per PCIe r4.0, sec 6.7.3.4, a "port may optionally send an MSI when there are hot-plug events that occur while interrupt generation is disabled, and interrupt generation is subsequently enabled." On probe, we currently clear all event bits in the Slot Status register with the notable exception of the Presence Detect Changed bit. Thereby we seek to receive an interrupt for an already occupied slot once event notification is enabled. But because the interrupt is optional, users may have to specify the pciehp_force parameter on the command line, which is inconvenient. Moreover, now that pciehp's event handling has become resilient to missed events, a Presence Detect Changed interrupt for a slot which is powered on is interpreted as removal of the card. If the slot has already been brought up by the BIOS, receiving such an interrupt on probe causes the slot to be powered off and immediately back on, which is likewise undesirable. Avoid both issues by making the behavior of pciehp_force the default and clearing the Presence Detect Changed bit on probe. Note that the stated purpose of pciehp_force per the MODULE_PARM_DESC ("Force pciehp, even if OSHP is missing") seems nonsensical because the OSHP control method is only relevant for SHCP slots according to the PCI Firmware specification r3.0, sec 4.8. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
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Lukas Wunner authored
A hotplug port's Slot Status register does not count how often each type of event occurred, it only records the fact *that* an event has occurred. Previously pciehp queued a work item for each event. But if it missed an event, e.g. removal of a card in-between two back-to-back insertions, it queued up the wrong work item or no work item at all. Commit fad214b0 ("PCI: pciehp: Process all hotplug events before looking for new ones") sought to improve the situation by shrinking the window during which events may be missed. But Stefan Roese reports unbalanced Card present and Link Up events, suggesting that we're still missing events if they occur very rapidly. Bjorn Helgaas responds that he considers pciehp's event handling "baroque" and calls for its simplification and rationalization: https://lkml.kernel.org/r/20180202192045.GA53759@bhelgaas-glaptop.roam.corp.google.com It gets worse once a hotplug port is runtime suspended: The port can signal an interrupt while it and its parents are in D3hot, i.e. while it is inaccessible. By the time we've runtime resumed all parents to D0 and read the port's Slot Status register, we may have missed an arbitrary number of events. Event handling therefore needs to be reworked to become resilient to missed events. Assume that a Presence Detect Changed event has occurred. Consider the following truth table: - Slot is in OFF_STATE and is currently empty. => Do nothing. (The event is trailing a Link Down or we've missed an insertion and subsequent removal.) - Slot is in OFF_STATE and is currently occupied. => Turn the slot on. - Slot is in ON_STATE and is currently empty. => Turn the slot off. - Slot is in ON_STATE and is currently occupied. => Turn the slot off, (Be cautious and assume the card in then back on. the slot isn't the same as before.) This leads to the following simple algorithm: 1 If the slot is in ON_STATE, turn it off unconditionally. 2 If the slot is currently occupied, turn it on. Because those actions are now carried out synchronously, rather than by scheduled work items, pciehp reacts to the *current* situation and missed events no longer matter. Data Link Layer State Changed events can be handled identically to Presence Detect Changed events. Note that in the above truth table, a Link Up trailing a Card present event didn't have to be accounted for: It is filtered out by pciehp_check_link_status(). As for Attention Button Pressed events, PCIe r4.0, sec 6.7.1.5 says: "Once the Power Indicator begins blinking, a 5-second abort interval exists during which a second depression of the Attention Button cancels the operation." In other words, the user can only expect the system to react to a button press after it starts blinking. Missed button presses that occur in-between are irrelevant. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefan Roese <sr@denx.de> Cc: Mayurkumar Patel <mayurkumar.patel@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
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Lukas Wunner authored
When a device is hotplugged, Presence Detect and Link Up events often do not occur simultaneously, but with a lag of a few milliseconds. Only the first event received is relevant, the other one can be disregarded. Moreover, Stefan Roese reports that on certain platforms, Link State and Presence Detect may flap for up to 100 ms before stabilizing, suggesting that such events should be disregarded for at least this long: https://lkml.kernel.org/r/20180130084121.18653-1-sr@denx.de On slot enablement, pciehp_check_link_status() waits for 100 ms per PCIe r4.0, sec 6.7.3.3, then probes the hotplugged device's vendor register for up to 1 second. If this succeeds, the link is definitely up, so ignore any Presence Detect or Link State events that occurred up to this point. pciehp_check_link_status() then checks the Link Training bit in the Link Status register. This is the final opportunity to detect inaccessibility of the device and abort slot enablement. Any link or presence change that occurs afterwards will cause the slot to be disabled again immediately after attempting to enable it. The astute reviewer may appreciate that achieving this behavior would be more complicated had pciehp not just been converted to enable/disable the slot exclusively from the IRQ thread: When the slot is enabled via sysfs, each link or presence flap would otherwise cause the IRQ thread to run and it would have to sense that those events are belonging to a concurrent slot enablement operation and disregard them. It would be much more difficult than this mere 3 line change. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefan Roese <sr@denx.de>
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Lukas Wunner authored
No callers of pciehp_enable/disable_slot() outside of pciehp_ctrl.c remain, so declare the functions static. For now this requires forward declarations. Those can be eliminated by reshuffling functions once the ongoing effort to refactor the driver has settled. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
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 5d386e1a ("pciehp: Event handling rework"), the latter in 2009 with commit 3aa551c9 ("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 fad214b0 ("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>
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Lukas Wunner authored
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>
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Lukas Wunner authored
Since commit 0f4bd801 ("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>
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Lukas Wunner authored
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/c16b4b14d980Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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Lukas Wunner authored
Commit b440bde7 ("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: b440bde7 ("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
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Lukas Wunner authored
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
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Lukas Wunner authored
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>
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Lukas Wunner authored
Ten years ago, commit 58319b80 ("PCI: Hotplug core: remove 'name'") dropped the name element from struct hotplug_slot but neglected to update the skeleton driver. That same year, commit f46753c5 ("PCI: introduce pci_slot") raised the number of arguments to pci_hp_register() from one to four. Fourteen years ago, historic commit 7ab60fc1 ("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>
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- 26 Jun, 2018 2 commits
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Bjorn Helgaas authored
The shpchp driver registers for all PCI bridge devices. Its probe method should fail if either (1) the bridge doesn't have an SHPC or (2) the OS isn't allowed to use it (the platform firmware may be operating the SHPC itself). Separate these two tests into: - A new shpc_capable() that looks for the SHPC hardware and is applicable on all systems (ACPI and non-ACPI), and - A simplified acpi_get_hp_hw_control_from_firmware() that we call only when we already know an SHPC exists and there may be ACPI methods to either request permission to use it (_OSC) or transfer control to the OS (OSHP). acpi_get_hp_hw_control_from_firmware() is implemented when CONFIG_ACPI=y, but does nothing if the current platform doesn't support ACPI. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
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Bjorn Helgaas authored
An SHPC can be operated either by platform firmware or by the OS. The OS uses a host bridge ACPI _OSC method to negotiate for control of SHPC. If firmware wants to prevent an OS from operating an SHPC, it must supply an _OSC method that declines to grant SHPC ownership to the OS. If acpi_pci_find_root() returns NULL, it means there's no ACPI host bridge device (PNP0A03 or PNP0A08) and hence no _OSC method, so the OS is always allowed to manage the SHPC. Fix a NULL pointer dereference when CONFIG_ACPI=y but the current hardware/firmware platform doesn't support ACPI. In that case, acpi_get_hp_hw_control_from_firmware() is implemented but acpi_pci_find_root() returns NULL. Fixes: 90cc0c3c ("PCI: shpchp: Add shpchp_is_native()") Link: https://lkml.kernel.org/r/20180621164715.28160-1-marc.zyngier@arm.comReported-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
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- 16 Jun, 2018 8 commits
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Linus Torvalds authored
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block fixes from Jens Axboe: "A collection of fixes that should go into -rc1. This contains: - bsg_open vs bsg_unregister race fix (Anatoliy) - NVMe pull request from Christoph, with fixes for regressions in this window, FC connect/reconnect path code unification, and a trace point addition. - timeout fix (Christoph) - remove a few unused functions (Christoph) - blk-mq tag_set reinit fix (Roman)" * tag 'for-linus-20180616' of git://git.kernel.dk/linux-block: bsg: fix race of bsg_open and bsg_unregister block: remov blk_queue_invalidate_tags nvme-fabrics: fix and refine state checks in __nvmf_check_ready nvme-fabrics: handle the admin-only case properly in nvmf_check_ready nvme-fabrics: refactor queue ready check blk-mq: remove blk_mq_tagset_iter nvme: remove nvme_reinit_tagset nvme-fc: fix nulling of queue data on reconnect nvme-fc: remove reinit_request routine blk-mq: don't time out requests again that are in the timeout handler nvme-fc: change controllers first connect to use reconnect path nvme: don't rely on the changed namespace list log nvmet: free smart-log buffer after use nvme-rdma: fix error flow during mapping request data nvme: add bio remapping tracepoint nvme: fix NULL pointer dereference in nvme_init_subsystem blk-mq: reinit q->tag_set_list entry only after grace period
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git://linuxtv.org/mchehab/experimentalLinus Torvalds authored
Pull documentation fixes from Mauro Carvalho Chehab: "This solves a series of broken links for files under Documentation, and improves a script meant to detect such broken links (see scripts/documentation-file-ref-check). The changes on this series are: - can.rst: fix a footnote reference; - crypto_engine.rst: Fix two parsing warnings; - Fix a lot of broken references to Documentation/*; - improve the scripts/documentation-file-ref-check script, in order to help detecting/fixing broken references, preventing false-positives. After this patch series, only 33 broken references to doc files are detected by scripts/documentation-file-ref-check" * tag 'docs-broken-links' of git://linuxtv.org/mchehab/experimental: (26 commits) fix a series of Documentation/ broken file name references Documentation: rstFlatTable.py: fix a broken reference ABI: sysfs-devices-system-cpu: remove a broken reference devicetree: fix a series of wrong file references devicetree: fix name of pinctrl-bindings.txt devicetree: fix some bindings file names MAINTAINERS: fix location of DT npcm files MAINTAINERS: fix location of some display DT bindings kernel-parameters.txt: fix pointers to sound parameters bindings: nvmem/zii: Fix location of nvmem.txt docs: Fix more broken references scripts/documentation-file-ref-check: check tools/*/Documentation scripts/documentation-file-ref-check: get rid of false-positives scripts/documentation-file-ref-check: hint: dash or underline scripts/documentation-file-ref-check: add a fix logic for DT scripts/documentation-file-ref-check: accept more wildcards at filenames scripts/documentation-file-ref-check: fix help message media: max2175: fix location of driver's companion documentation media: v4l: fix broken video4linux docs locations media: dvb: point to the location of the old README.dvb-usb file ...
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git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fsLinus Torvalds authored
Pull fsnotify updates from Jan Kara: "fsnotify cleanups unifying handling of different watch types. This is the shortened fsnotify series from Amir with the last five patches pulled out. Amir has modified those patches to not change struct inode but obviously it's too late for those to go into this merge window" * tag 'fsnotify_for_v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: add fsnotify_add_inode_mark() wrappers fanotify: generalize fanotify_should_send_event() fsnotify: generalize send_to_group() fsnotify: generalize iteration of marks by object type fsnotify: introduce marks iteration helpers fsnotify: remove redundant arguments to handle_event() fsnotify: use type id to identify connector object type
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git://github.com/bzolnier/linuxLinus Torvalds authored
Pull fbdev updates from Bartlomiej Zolnierkiewicz: "There is nothing really major here, few small fixes, some cleanups and dead drivers removal: - mark omapfb drivers as orphans in MAINTAINERS file (Tomi Valkeinen) - add missing module license tags to omap/omapfb driver (Arnd Bergmann) - add missing GPIOLIB dependendy to omap2/omapfb driver (Arnd Bergmann) - convert savagefb, aty128fb & radeonfb drivers to use msleep & co. (Jia-Ju Bai) - allow COMPILE_TEST build for viafb driver (media part was reviewed by media subsystem Maintainer) - remove unused MERAM support from sh_mobile_lcdcfb and shmob-drm drivers (drm parts were acked by shmob-drm driver Maintainer) - remove unused auo_k190xfb drivers - misc cleanups (Souptick Joarder, Wolfram Sang, Markus Elfring, Andy Shevchenko, Colin Ian King)" * tag 'fbdev-v4.18' of git://github.com/bzolnier/linux: (26 commits) fb_omap2: add gpiolib dependency video/omap: add module license tags MAINTAINERS: make omapfb orphan video: fbdev: pxafb: match_string() conversion fixup video: fbdev: nvidia: fix spelling mistake: "scaleing" -> "scaling" video: fbdev: fix spelling mistake: "frambuffer" -> "framebuffer" video: fbdev: pxafb: Convert to use match_string() helper video: fbdev: via: allow COMPILE_TEST build video: fbdev: remove unused sh_mobile_meram driver drm: shmobile: remove unused MERAM support video: fbdev: sh_mobile_lcdcfb: remove unused MERAM support video: fbdev: remove unused auo_k190xfb drivers video: omap: Improve a size determination in omapfb_do_probe() video: sm501fb: Improve a size determination in sm501fb_probe() video: fbdev-MMP: Improve a size determination in path_init() video: fbdev-MMP: Delete an error message for a failed memory allocation in two functions video: auo_k190x: Delete an error message for a failed memory allocation in auok190x_common_probe() video: sh_mobile_lcdcfb: Delete an error message for a failed memory allocation in two functions video: sh_mobile_meram: Delete an error message for a failed memory allocation in sh_mobile_meram_probe() video: fbdev: sh_mobile_meram: Drop SUPERH platform dependency ...
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull AFS updates from Al Viro: "Assorted AFS stuff - ended up in vfs.git since most of that consists of David's AFS-related followups to Christoph's procfs series" * 'afs-proc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: afs: Optimise callback breaking by not repeating volume lookup afs: Display manually added cells in dynamic root mount afs: Enable IPv6 DNS lookups afs: Show all of a server's addresses in /proc/fs/afs/servers afs: Handle CONFIG_PROC_FS=n proc: Make inline name size calculation automatic afs: Implement network namespacing afs: Mark afs_net::ws_cell as __rcu and set using rcu functions afs: Fix a Sparse warning in xdr_decode_AFSFetchStatus() proc: Add a way to make network proc files writable afs: Rearrange fs/afs/proc.c to remove remaining predeclarations. afs: Rearrange fs/afs/proc.c to move the show routines up afs: Rearrange fs/afs/proc.c by moving fops and open functions down afs: Move /proc management functions to the end of the file
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull compat updates from Al Viro: "Some biarch patches - getting rid of assorted (mis)uses of compat_alloc_user_space(). Not much in that area this cycle..." * 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: orangefs: simplify compat ioctl handling signalfd: lift sigmask copyin and size checks to callers of do_signalfd4() vmsplice(): lift importing iovec into vmsplice(2) and compat counterpart
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull aio fixes from Al Viro: "Assorted AIO followups and fixes" * 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: eventpoll: switch to ->poll_mask aio: only return events requested in poll_mask() for IOCB_CMD_POLL eventfd: only return events requested in poll_mask() aio: mark __aio_sigset::sigmask const
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- 15 Jun, 2018 7 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Various netfilter fixlets from Pablo and the netfilter team. 2) Fix regression in IPVS caused by lack of PMTU exceptions on local routes in ipv6, from Julian Anastasov. 3) Check pskb_trim_rcsum for failure in DSA, from Zhouyang Jia. 4) Don't crash on poll in TLS, from Daniel Borkmann. 5) Revert SO_REUSE{ADDR,PORT} change, it regresses various things including Avahi mDNS. From Bart Van Assche. 6) Missing of_node_put in qcom/emac driver, from Yue Haibing. 7) We lack checking of the TCP checking in one special case during SYN receive, from Frank van der Linden. 8) Fix module init error paths of mac80211 hwsim, from Johannes Berg. 9) Handle 802.1ad properly in stmmac driver, from Elad Nachman. 10) Must grab HW caps before doing quirk checks in stmmac driver, from Jose Abreu. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits) net: stmmac: Run HWIF Quirks after getting HW caps neighbour: skip NTF_EXT_LEARNED entries during forced gc net: cxgb3: add error handling for sysfs_create_group tls: fix waitall behavior in tls_sw_recvmsg tls: fix use-after-free in tls_push_record l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl() l2tp: reject creation of non-PPP sessions on L2TPv2 tunnels mlxsw: spectrum_switchdev: Fix port_vlan refcounting mlxsw: spectrum_router: Align with new route replace logic mlxsw: spectrum_router: Allow appending to dev-only routes ipv6: Only emit append events for appended routes stmmac: added support for 802.1ad vlan stripping cfg80211: fix rcu in cfg80211_unregister_wdev mac80211: Move up init of TXQs mac80211_hwsim: fix module init error paths cfg80211: initialize sinfo in cfg80211_get_station nl80211: fix some kernel doc tag mistakes hv_netvsc: Fix the variable sizes in ipsecv2 and rsc offload rds: avoid unenecessary cong_update in loop transport l2tp: clean up stale tunnel or session in pppol2tp_connect's error path ...
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git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linuxLinus Torvalds authored
Pull module updates from Jessica Yu: "Minor code cleanup and also allow sig_enforce param to be shown in sysfs with CONFIG_MODULE_SIG_FORCE" * tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: Allow to always show the status of modsign module: Do not access sig_enforce directly
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git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds authored
Pull uml updates from Richard Weinberger: "Minor updates for UML: - fixes for our new vector network driver by Anton - initcall cleanup by Alexander - We have a new mailinglist, sourceforge.net sucks" * 'for-linus-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: Fix raw interface options um: Fix initialization of vector queues um: remove uml initcalls um: Update mailing list address
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Linus Torvalds authored
Merge tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains some small RISC-V updates I'd like to target for 4.18. They are all fairly small this time. Here's a short summary, there's more info in the commits/merges: - a fix to __clear_user to respect the passed arguments. - enough support for the perf subsystem to work with RISC-V's ISA defined performance counters. - support for sparse and cleanups suggested by it. - support for R_RISCV_32 (a relocation, not the 32-bit ISA). - some MAINTAINERS cleanups. - the addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's always present. I've given these a simple build+boot test" * tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: RISC-V: Add CONFIG_HVC_RISCV_SBI=y to defconfig RISC-V: Handle R_RISCV_32 in modules riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set riscv: add riscv-specific predefines to CHECKFLAGS riscv: split the declaration of __copy_user riscv: no __user for probe_kernel_address() riscv: use NULL instead of a plain 0 perf: riscv: Add Document for Future Porting Guide perf: riscv: preliminary RISC-V support MAINTAINERS: Update Albert's email, he's back at Berkeley MAINTAINERS: Add myself as a maintainer for SiFive's drivers riscv: Fix the bug in memory access fixup code
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull more kvm updates from Paolo Bonzini: "Mostly the PPC part of the release, but also switching to Arnd's fix for the hyperv config issue and a typo fix. Main PPC changes: - reimplement the MMIO instruction emulation - transactional memory support for PR KVM - improve radix page table handling" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (63 commits) KVM: x86: VMX: redo fix for link error without CONFIG_HYPERV KVM: x86: fix typo at kvm_arch_hardware_setup comment KVM: PPC: Book3S PR: Fix failure status setting in tabort. emulation KVM: PPC: Book3S PR: Enable use on POWER9 bare-metal hosts in HPT mode KVM: PPC: Book3S PR: Don't let PAPR guest set MSR hypervisor bit KVM: PPC: Book3S PR: Fix failure status setting in treclaim. emulation KVM: PPC: Book3S PR: Fix MSR setting when delivering interrupts KVM: PPC: Book3S PR: Handle additional interrupt types KVM: PPC: Book3S PR: Enable kvmppc_get/set_one_reg_pr() for HTM registers KVM: PPC: Book3S: Remove load/put vcpu for KVM_GET_REGS/KVM_SET_REGS KVM: PPC: Remove load/put vcpu for KVM_GET/SET_ONE_REG ioctl KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl KVM: PPC: Book3S PR: Enable HTM for PR KVM for KVM_CHECK_EXTENSION ioctl KVM: PPC: Book3S PR: Support TAR handling for PR KVM HTM KVM: PPC: Book3S PR: Add guard code to prevent returning to guest with PR=0 and Transactional state KVM: PPC: Book3S PR: Add emulation for tabort. in privileged state KVM: PPC: Book3S PR: Add emulation for trechkpt. KVM: PPC: Book3S PR: Add emulation for treclaim. KVM: PPC: Book3S PR: Restore NV regs after emulating mfspr from TM SPRs KVM: PPC: Book3S PR: Always fail transactions in guest privileged state ...
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git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds authored
Pull virtio updates from Michael Tsirkin: "virtio, vhost: features, fixes - PCI virtual function support for virtio - DMA barriers for virtio strong barriers - bugfixes" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio: update the comments for transport features virtio_pci: support enabling VFs vhost: fix info leak due to uninitialized memory virtio_ring: switch to dma_XX barriers for rpmsg
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Mauro Carvalho Chehab authored
As files move around, their previous links break. Fix the references for them. Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
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