Commit Graph

54 Commits

Author SHA1 Message Date
Lukas Wunner
9d573d1954 PCI: pciehp: Detect device replacement during system sleep
Ricky reports that replacing a device in a hotplug slot during ACPI sleep
state S3 does not cause re-enumeration on resume, as one would expect.
Instead, the new device is treated as if it was the old one.

There is no bulletproof way to detect device replacement, but as a
heuristic, check whether the device identity in config space matches cached
data in struct pci_dev (Vendor ID, Device ID, Class Code, Revision ID,
Subsystem Vendor ID, Subsystem ID).  Additionally, cache and compare the
Device Serial Number (PCIe r6.2 sec 7.9.3).  If a mismatch is detected,
mark the old device disconnected (to prevent its driver from accessing the
new device) and synthesize a Presence Detect Changed event.

The device identity in config space which is compared here is the same as
the one included in the signed Subject Alternative Name per PCIe r6.1 sec
6.31.3.  Thus, the present commit prevents attacks where a valid device is
replaced with a malicious device during system sleep and the valid device's
driver obliviously accesses the malicious device.

This is about as much as can be done at the PCI layer.  Drivers may have
additional ways to identify devices (such as reading a WWID from some
register) and may trigger re-enumeration when detecting an identity change
on resume.

Link: https://lore.kernel.org/r/a1afaa12f341d146ecbea27c1743661c71683833.1716992815.git.lukas@wunner.de
Reported-by: Ricky Wu <ricky_wu@realtek.com>
Closes: https://lore.kernel.org/r/a608b5930d0a48f092f717c0e137454b@realtek.com
Tested-by: Ricky Wu <ricky_wu@realtek.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2024-05-30 12:17:34 -05:00
Lukas Wunner
f5eff5591b PCI: pciehp: Fix AB-BA deadlock between reset_lock and device_lock
In 2013, commits

  2e35afaefe ("PCI: pciehp: Add reset_slot() method")
  608c388122 ("PCI: Add slot reset option to pci_dev_reset()")

amended PCIe hotplug to mask Presence Detect Changed events during a
Secondary Bus Reset.  The reset thus no longer causes gratuitous slot
bringdown and bringup.

However the commits neglected to serialize reset with code paths reading
slot registers.  For instance, a slot bringup due to an earlier hotplug
event may see the Presence Detect State bit cleared during a concurrent
Secondary Bus Reset.

In 2018, commit

  5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")

retrofitted the missing locking.  It introduced a reset_lock which
serializes a Secondary Bus Reset with other parts of pciehp.

Unfortunately the locking turns out to be overzealous:  reset_lock is
held for the entire enumeration and de-enumeration of hotplugged devices,
including driver binding and unbinding.

Driver binding and unbinding acquires device_lock while the reset_lock
of the ancestral hotplug port is held.  A concurrent Secondary Bus Reset
acquires the ancestral reset_lock while already holding the device_lock.
The asymmetric locking order in the two code paths can lead to AB-BA
deadlocks.

Michael Haeuptle reports such deadlocks on simultaneous hot-removal and
vfio release (the latter implies a Secondary Bus Reset):

  pciehp_ist()                                    # down_read(reset_lock)
    pciehp_handle_presence_or_link_change()
      pciehp_disable_slot()
        __pciehp_disable_slot()
          remove_board()
            pciehp_unconfigure_device()
              pci_stop_and_remove_bus_device()
                pci_stop_bus_device()
                  pci_stop_dev()
                    device_release_driver()
                      device_release_driver_internal()
                        __device_driver_lock()    # device_lock()

  SYS_munmap()
    vfio_device_fops_release()
      vfio_device_group_close()
        vfio_device_close()
          vfio_device_last_close()
            vfio_pci_core_close_device()
              vfio_pci_core_disable()             # device_lock()
                __pci_reset_function_locked()
                  pci_reset_bus_function()
                    pci_dev_reset_slot_function()
                      pci_reset_hotplug_slot()
                        pciehp_reset_slot()       # down_write(reset_lock)

Ian May reports the same deadlock on simultaneous hot-removal and an
AER-induced Secondary Bus Reset:

  aer_recover_work_func()
    pcie_do_recovery()
      aer_root_reset()
        pci_bus_error_reset()
          pci_slot_reset()
            pci_slot_lock()                       # device_lock()
            pci_reset_hotplug_slot()
              pciehp_reset_slot()                 # down_write(reset_lock)

Fix by releasing the reset_lock during driver binding and unbinding,
thereby splitting and shrinking the critical section.

Driver binding and unbinding is protected by the device_lock() and thus
serialized with a Secondary Bus Reset.  There's no need to additionally
protect it with the reset_lock.  However, pciehp does not bind and
unbind devices directly, but rather invokes PCI core functions which
also perform certain enumeration and de-enumeration steps.

The reset_lock's purpose is to protect slot registers, not enumeration
and de-enumeration of hotplugged devices.  That would arguably be the
job of the PCI core, not the PCIe hotplug driver.  After all, an
AER-induced Secondary Bus Reset may as well happen during boot-time
enumeration of the PCI hierarchy and there's no locking to prevent that
either.

Exempting *de-enumeration* from the reset_lock is relatively harmless:
A concurrent Secondary Bus Reset may foil config space accesses such as
PME interrupt disablement.  But if the device is physically gone, those
accesses are pointless anyway.  If the device is physically present and
only logically removed through an Attention Button press or the sysfs
"power" attribute, PME interrupts as well as DMA cannot come through
because pciehp_unconfigure_device() disables INTx and Bus Master bits.
That's still protected by the reset_lock in the present commit.

Exempting *enumeration* from the reset_lock also has limited impact:
The exempted call to pci_bus_add_device() may perform device accesses
through pcibios_bus_add_device() and pci_fixup_device() which are now
no longer protected from a concurrent Secondary Bus Reset.  Otherwise
there should be no impact.

In essence, the present commit seeks to fix the AB-BA deadlocks while
still retaining a best-effort reset protection for enumeration and
de-enumeration of hotplugged devices -- until a general solution is
implemented in the PCI core.

Link: https://lore.kernel.org/linux-pci/CS1PR8401MB0728FC6FDAB8A35C22BD90EC95F10@CS1PR8401MB0728.NAMPRD84.PROD.OUTLOOK.COM
Link: https://lore.kernel.org/linux-pci/20200615143250.438252-1-ian.may@canonical.com
Link: https://lore.kernel.org/linux-pci/ce878dab-c0c4-5bd0-a725-9805a075682d@amd.com
Link: https://lore.kernel.org/linux-pci/ed831249-384a-6d35-0831-70af191e9bce@huawei.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215590
Fixes: 5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")
Link: https://lore.kernel.org/r/fef2b2e9edf245c049a8c5b94743c0f74ff5008a.1681191902.git.lukas@wunner.de
Reported-by: Michael Haeuptle <michael.haeuptle@hpe.com>
Reported-by: Ian May <ian.may@canonical.com>
Reported-by: Andrey Grodzovsky <andrey2805@gmail.com>
Reported-by: Rahul Kumar <rahul.kumar1@amd.com>
Reported-by: Jialin Zhang <zhangjialin11@huawei.com>
Tested-by: Anatoli Antonovitch <Anatoli.Antonovitch@amd.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v4.19+
Cc: Dan Stein <dstein@hpe.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Alex Michon <amichon@kalrayinc.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>
2023-04-11 13:18:30 -05:00
Frederick Lawler
94dbc9562e PCI: pciehp: Log messages with pci_dev, not pcie_device
Log messages with pci_dev, not pcie_device.  Factor out common message
prefixes with dev_fmt().

Example output change:

  - pciehp 0000:00:06.0:pcie004: Slot(0) Powering on due to button press
  + pcieport 0000:00:06.0: pciehp: Slot(0) Powering on due to button press

Link: https://lore.kernel.org/lkml/20190509141456.223614-8-helgaas@kernel.org
Signed-off-by: Frederick Lawler <fred@fredlawl.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2019-05-09 16:45:20 -05:00
Lukas Wunner
5790a9c78e PCI: pciehp: Unify controller and slot structs
pciehp was originally introduced together with shpchp in a single
commit, c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug
drivers"):
https://git.kernel.org/tglx/history/c/c16b4b14d980

shpchp supports up to 31 slots per controller, hence uses separate slot
and controller structs.  pciehp has a 1:1 relationship between slot and
controller and therefore never required this separation.  Nevertheless,
because much of the code had been copy-pasted between the two drivers,
pciehp likewise uses separate structs to this very day.

The artificial separation of data structures adds unnecessary complexity
and bloat to pciehp and requires constantly chasing pointers at runtime.

Simplify the driver by merging struct slot into struct controller.
Merge the slot constructor pcie_init_slot() and the destructor
pcie_cleanup_slot() into the controller counterparts.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-18 17:52:15 -05:00
Lukas Wunner
7d4ba52317 PCI: pciehp: Drop unnecessary includes
Drop the following includes from pciehp source files which no longer use
any of the included symbols:

* <linux/sched/signal.h> in pciehp.h
  <linux/signal.h> in pciehp_hpc.c
  Added by commit de25968cc8 ("fix more missing includes") to
  accommodate for a call to signal_pending().
  The call was removed by commit 262303fe32 ("pciehp: fix wait command
  completion").

* <linux/interrupt.h> in pciehp_core.c
  Added by historic commit f308a2dfbe63 ("PCI: add PCI Express Port Bus
  Driver subsystem") to accommodate for a call to free_irq():
  https://git.kernel.org/tglx/history/c/f308a2dfbe63
  The call was removed by commit 407f452b05 ("pciehp: remove
  unnecessary free_irq").

* <linux/time.h> in pciehp_core.c and pciehp_hpc.c
  Added by commit 34d03419f0 ("PCIEHP: Add Electro Mechanical
  Interlock (EMI) support to the PCIE hotplug driver."),
  which was reverted by commit bd3d99c170 ("PCI: Remove untested
  Electromechanical Interlock (EMI) support in pciehp.").

* <linux/module.h> in pciehp_ctrl.c, pciehp_hpc.c and pciehp_pci.c
  Added by historic commit c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI
  Express hot-plug drivers"):
  https://git.kernel.org/tglx/history/c/c16b4b14d980
  Module-related symbols were neither used back then in those files,
  nor are they used today.

* <linux/slab.h> in pciehp_ctrl.c
  Added by commit 5a0e3ad6af ("include cleanup: Update gfp.h and
  slab.h includes to prepare for breaking implicit slab.h inclusion from
  percpu.h") to accommodate for calls to kmalloc().
  The calls were removed by commit 0e94916e60 ("PCI: pciehp: Handle
  events synchronously").

* "../pci.h" in pciehp_ctrl.c
  Added by historic commit 67f4660b72f2 ("PCI: ASPM patch for") to
  accommodate for usage of the global variable pcie_mch_quirk:
  https://git.kernel.org/tglx/history/c/67f4660b72f2
  The global variable was removed by commit 0ba379ec0f ("PCI: Simplify
  hotplug mch quirk").

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-17 16:34:36 -05:00
Lukas Wunner
11e87702be PCI: pciehp: Differentiate between surprise and safe removal
When removing PCI devices below a hotplug bridge, pciehp marks them as
disconnected if the card is no longer present in the slot or it quiesces
them if the card is still present (by disabling INTx interrupts, bus
mastering and SERR# reporting).

To detect whether the card is still present, pciehp checks the Presence
Detect State bit in the Slot Status register.  The problem with this
approach is that even if the card is present, the link to it may be
down, and it that case it would be better to mark the devices as
disconnected instead of trying to quiesce them.  Moreover, if the card
in the slot was quickly replaced by another one, the Presence Detect
State bit would be set, yet trying to quiesce the new card's devices
would be wrong and the correct thing to do is to mark the previous
card's devices as disconnected.

Instead of looking at the Presence Detect State bit, it is better to
differentiate whether the card was surprise removed versus safely
removed (via sysfs or an Attention Button press).  On surprise removal,
the devices should be marked as disconnected, whereas on safe removal it
is correct to quiesce the devices.

The knowledge whether a surprise removal or a safe removal is at hand
does exist further up in the call stack:  A surprise removal is
initiated by pciehp_handle_presence_or_link_change(), a safe removal by
pciehp_handle_disable_request().

Pass that information down to pciehp_unconfigure_device() and use it in
lieu of the Presence Detect State bit.  While there, add kernel-doc to
pciehp_unconfigure_device() and pciehp_configure_device().

Tested-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Keith Busch <keith.busch@intel.com>
2018-09-17 16:34:35 -05:00
Lukas Wunner
a50ac6bfd6 PCI: Simplify disconnected marking
Commit 89ee9f7680 ("PCI: Add device disconnected state") iterates over
the devices on a parent bus, marks each as disconnected, then marks
each device's children as disconnected using pci_walk_bus().

The same can be achieved more succinctly by calling pci_walk_bus() on
the parent bus.  Moreover, this does not need to wait until acquiring
pci_lock_rescan_remove(), so move it out of that critical section.

The critical section in err.c contains a pci_dev_get() / pci_dev_put()
pair which was apparently copy-pasted from pciehp_pci.c.  In the latter
it serves the purpose of holding the struct pci_dev in place until the
Command register is updated.  err.c doesn't do anything like that, hence
the pair is unnecessary.  Remove it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Oza Pawandeep <poza@codeaurora.org>
Cc: Sinan Kaya <okaya@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2018-09-17 16:34:35 -05:00
Lukas Wunner
1d2e2673dc PCI: pciehp: Declare pciehp_unconfigure_device() void
Since commit 0f4bd8014d ("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>
2018-07-23 17:04:11 -05:00
Bjorn Helgaas
ab8c609356 Merge branch 'pci/spdx' into next
* pci/spdx:
  PCI: Add SPDX GPL-2.0+ to replace implicit GPL v2 or later statement
  PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
  PCI: Add SPDX GPL-2.0 to replace COPYING boilerplate
  PCI: Add SPDX GPL-2.0 to replace GPL v2 boilerplate
  PCI: Add SPDX GPL-2.0 when no license was specified
2018-02-01 11:40:07 -06:00
Bjorn Helgaas
736759ef59 PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed
either GPL version 2 or any later version.

Remove the boilerplate GPL version 2 or later language, relying on the
assertion in b24413180f ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") that the SPDX identifier may be used
instead of the full boilerplate text.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-28 15:49:06 -06:00
Mika Westerberg
0f4bd8014d PCI: hotplug: Drop checking of PCI_BRIDGE_CONTROL in *_unconfigure_device()
When removing a bridge, pciehp_unconfigure_device() reads the
PCI_BRIDGE_CONTROL byte.  If this is a surprise hot-unplug, the device is
already gone and the read returns ~0, which pciehp_unconfigure_device()
interprets as having PCI_BRIDGE_CTL_VGA set.  This results in failure of
the remove operation:

  pciehp 0000:00:1c.0:pcie004: Slot(0): Link Down
  pciehp 0000:00:1c.0:pcie004: Slot(0): Card present
  pciehp 0000:00:1c.0:pcie004: Cannot remove display device 0000:01:00.0

Because of this the hierarchy is left untouched preventing further hotplug
operations.

Now, it is not clear why the check is there in the first place and why we
would like to prevent removing a bridge if it has PCI_BRIDGE_CTL_VGA set.
In case of PCIe surprise hot-unplug, it would not even be possible to
prevent the removal.

Given this and the issue described above, I think it makes sense to drop
the whole PCI_BRIDGE_CONTROL check from pciehp_unconfigure_device().  While
there do the same for shpchp_configure_device() based on the same reasoning
and the fact that the same bug might trigger in standard PCI hotplug as
well.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-12-18 23:05:18 -06:00
Mika Westerberg
499022396a PCI: pciehp: Fix race condition handling surprise link down
A surprise link down may retrain very quickly causing the same slot
generate a link up event before handling the link down event completes.

Since the link is active, the power off work queued from the first link
down will cause a second down event when power is disabled. However, the
link up event sets the slot state to POWERON_STATE before the event to
handle this is enqueued, making the second down event believe it needs to
do something.

This creates constant link up and down event cycle.

To prevent this it is better to handle each event at the time in order it
occurred, so change the driver to use ordered workqueue instead.

A normal device hotplug triggers two events (presense detect and link up)
that are already handled properly in the driver but we currently log an
error if we find an existing device in the slot. Since this is not an error
change the log level to be debug instead to avoid scaring users.

This is based on the original work by Ashok Raj.

Link: https://patchwork.kernel.org/patch/9469023
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06 18:49:00 -06:00
Andy Shevchenko
24a0c654d7 PCI: Add for_each_pci_bridge() helper
The following pattern is often used:

  list_for_each_entry(dev, &bus->devices, bus_list) {
    if (pci_is_bridge(dev)) {
      ...
    }
  }

Add a for_each_pci_bridge() helper to make that code easier to write and
read by reducing indentation level.  It also saves one or few lines of code
in each occurrence.

Convert PCI core parts here at the same time.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: fold in http://lkml.kernel.org/r/20171013165352.25550-1-andriy.shevchenko@linux.intel.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06 18:48:58 -06:00
Keith Busch
89ee9f7680 PCI: Add device disconnected state
Add a new state to pci_dev to be set when it is unexpectedly disconnected.
The PCI driver tear down functions can observe this new device state so
they may skip operations that will fail.

The pciehp and pcie-dpc drivers are aware when the link is down, so these
set the flag when their handlers detect the device is disconnected.

Tested-by: Krishna Dhulipala <krishnad@fb.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Wei Zhang <wzhang@fb.com>
2017-03-29 22:54:46 -05:00
Bjorn Helgaas
77094fb342 PCI: pciehp: Remove pci_configure_slot() usage
We now configure each PCI device as it is enumerated, in pci_device_add(),
so remove the configuration done in pciehp.

That configuration, in pci_configure_device(), does not include the
MPS/MRRS configuration done by pcie_bus_configure_settings(), so keep
that here.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
2014-09-12 20:09:47 -06:00
Bjorn Helgaas
1197ba22c5 PCI: pciehp: Configure hot-added display devices
We configure cache line size and other settings of hot-added devices, e.g.,
based on ACPI _HPP or _HPX methods.  Previously we skipped this for display
devices, but ACPI rev 5.0, sec 6.2.7 and 6.2.8 have no requirement to skip
them.

Remove the check so we configure display devices the same way we configure
other devices.

See also ac81860ea0 ("PCI: hotplug: pciehp: Removed check for hotplug of
display devices").

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
2014-09-12 20:01:20 -06:00
Ryan Desfosses
227f064705 PCI: Merge multi-line quoted strings
Merge quoted strings that are broken across lines into a single entity.
The compiler merges them anyway, but checkpatch complains about it, and
merging them makes it easier to grep for strings.

No functional change.

[bhelgaas: changelog, do the same for everything under drivers/pci]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-10 20:20:42 -06:00
Yijing Wang
930067e235 PCI: pciehp: Use pci_is_bridge() to simplify code
Use pci_is_bridge() to simplify code.  No functional change.

Requires: 326c1cdae7 PCI: Rename pci_is_bridge() to pci_has_subordinate()
Requires: 1c86438c94 PCI: Add new pci_is_bridge() interface
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-05-27 14:58:18 -06:00
Yijing Wang
50277c8b06 PCI: pciehp: Don't turn slot off when hot-added device already exists
If we found device already exists during hot add device, we should leave
it, not turn the slot off.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-14 10:13:56 -07:00
Rafael J. Wysocki
c4ec84c7db PCI: hotplug: Use global PCI rescan-remove locking
Multiple race conditions are possible between PCI hotplug and the generic
PCI bus rescan and device removal that can be triggered via sysfs.

To avoid those race conditions make PCI hotplug use global PCI
rescan-remove locking.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-14 12:14:25 -07:00
Bjorn Helgaas
6dae62020f PCI: pciehp: Make various functions void since they can't fail
These functions:

  pcie_enable_notification()
  pciehp_power_off_slot()
  pciehp_get_power_status()
  pciehp_get_attention_status()
  pciehp_set_attention_status()
  pciehp_get_latch_status()
  pciehp_get_adapter_status()
  pcie_write_cmd()

now always return success, so this patch makes them void and drops the
error-checking code in their callers.

No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-12-15 16:07:32 -07:00
Yinghai Lu
29ed1f29b6 PCI: pciehp: Fix null pointer deref when hot-removing SR-IOV device
Hot-removing a device with SR-IOV enabled causes a null pointer dereference
in v3.9 and v3.10.

This is a regression caused by ba518e3c17 ("PCI: pciehp: Iterate over all
devices in slot, not functions 0-7").  When we iterate over the
bus->devices list, we first remove the PF, which also removes all the VFs
from the list.  Then the list iterator blows up because more than just the
current entry was removed from the list.

ac205b7bb7 ("PCI: make sriov work with hotplug remove") works around a
similar problem in pci_stop_bus_devices() by iterating over the list in
reverse, so the VFs are stopped and removed from the list first, before the
PF.

This patch changes pciehp_unconfigure_device() to iterate over the list in
reverse, too.

[bhelgaas: bugzilla, changelog]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=60604
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yijing Wang <wangyijing@huawei.com>
CC: stable@vger.kernel.org	# v3.9+
2013-07-25 14:11:06 -06:00
Yijing Wang
ba518e3c17 PCI: pciehp: Iterate over all devices in slot, not functions 0-7
Currently, we enumerate devices in a slot with pci_scan_slot(), then
iterate through all the devices we found by looking for functions 0-7.  But
that's wrong for ARI devices, which may have function numbers up to 255.

This means that when we hot-add an ARI device, pciehp only initializes
functions 0-7, and other functions don't work correctly.  Additionally, if
we hot-remove the device, pciehp only removes functions 0-7, leaving stale
pci_dev structures for any other functions.

This patch fixes the problem by iterating over devices in a slot by using
the upstream bridge's "bus->devices" list instead.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-25 09:21:10 -07:00
Yinghai Lu
c6da81a4d3 PCI: pciehp: use generic pci_hp_add_bridge()
Use the new generic pci_hp_add_bridge() interface.

[bhelgaas: split "add generic pci_hp_add_bridge()" into a separate patch]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-06-13 15:42:26 -06:00
Yinghai Lu
b918c62e08 PCI: replace struct pci_bus secondary/subordinate with busn_res
Replace the struct pci_bus secondary/subordinate members with the
struct resource busn_res.  Later we'll build a resource tree of these
bus numbers.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-06-13 15:42:22 -06:00
Yinghai Lu
210647af89 PCI: Rename pci_remove_bus_device to pci_stop_and_remove_bus_device
The old pci_remove_bus_device actually did stop and remove.

Make the name reflect that to reduce confusion.

This patch is done by sed scripts and changes back some incorrect
__pci_remove_bus_device changes.

Suggested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-02-27 12:12:18 -08:00
Praveen Kalamegham
01b666df48 PCI hotplug: pciehp: Fixed return value sign for pciehp_unconfigure_device
pciehp_unconfigure_device() should return -EINVAL, not EINVAL.

Signed-off-by: Praveen Kalamegham <praveen@nextio.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-07-30 09:29:15 -07:00
Praveen Kalamegham
ac81860ea0 PCI: hotplug: pciehp: Removed check for hotplug of display devices
Removed check to prevent hotplug of display devices within pciehp.
Originally this was thought to have been required within the PCI
Hotplug specification for some legacy devices.  However there is
no such requirement in the most recent revision. The check prevents
hotplug of not only display devices but also computational GPUs
which require serviceability.

Signed-off-by: Praveen Kalamegham <praveen@nextio.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-05-21 14:43:46 -07:00
Yinghai Lu
9789ac979b PCI: pciehp: cleanup flow in pciehp_configure_device
Move bus_size_bridges and assign resources out of pciehp_add_bridge()
and do them all together, one time, including slot bridge, to avoid to
calling assign resources several times when there are several bridges
under the slot bridge.  Using pci_assign_unassigned_bridge_resources.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22 16:17:24 -08:00
Kenji Kaneshige
82a9e79ef1 PCI: pciehp: remove hpc_ops
The struct hpc_ops seems a set of hooks to controller specific
routines. But, it is meaningless because no hotplug controller driver
follows this framework.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:31 -07:00
Kenji Kaneshige
385e24917e PCI: pciehp: remove pci_dev field
Since we have a pointer to pcie_device in struct controller, we don't
need a pointer to pci_dev.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:06:25 -07:00
Kenji Kaneshige
d689f7eb36 PCI: pciehp: remove device field
The device field in the struct slot is not necessary because it is
always 0 in pciehp driver.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:51 -07:00
Kenji Kaneshige
ab9c6c8670 PCI: pciehp: remove bus field
The bus field in struct slot is not necessary.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17 10:05:46 -07:00
Bjorn Helgaas
d569c74d78 PCI hotplug: pciehp: use generic pci_configure_slot()
Use the generic pci_configure_slot() rather than the PCIe-specific
program_fw_provided_values().

Unlike the previous pciehp-specific code, we now walk through subordinate
devices even if there are no settings for the parent.  This should be
harmless because we won't change anything unless we discover firmware
settings farther down.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-14 17:39:09 -07:00
Eric W. Biederman
0ba379ec0f PCI: Simplify hotplug mch quirk.
There is a very old quirk for the intel E7502 E7320 and E7525 memory
controller hubs that disables usage of msi interrupts on pcie hotplug
bridges of those devices, and disables changing the affinity of irqs.

Today all we have to do to disable msi on a specific device is to set
dev->no_msi, which is much more straightforward than the previous
logic.

The re-running of this fixup after pci hotplug happens below these
devices is totally bogus.  All of the state we change is pure software
state and we don't change the hardware at all.  Which means hotplug on
the lower devices doesn't have a chance to change this state.  So we
can safely remove the special case from the pciehp driver and the pcie
portdriver.

I suspect the special case was someone's expermental debug code that
slipped in. Certainly it isn't mentioned in commit
6fb8880a61510295aece04a542767161f624dffe aka BKrev:
41966101LJ_ogfOU0m2aE6teZfQnuQ where the code first appears.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 14:06:49 -07:00
Taku Izumi
18b341b76c PCI hotplug: pciehp: message refinement
This patch refines messages in pciehp module.  The main changes are as
follows:

 - remove the trailing "."
 - remove __func__ as much as possible
 - capitalize the first letter of messages
 - show PCI device address including its domain

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-23 14:47:39 -07:00
Taku Izumi
7f2feec140 PCI: pciehp: replace printk with dev_printk
This patch replaces printks within pciehp module with dev_printks.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-10-20 10:53:49 -07:00
Harvey Harrison
66bef8c059 PCI: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-20 21:47:09 -07:00
Sam Ravnborg
0ab2b57f8d PCI: fix section mismatch warning in pci_scan_child_bus
Fix following warning:
WARNING: vmlinux.o(.text+0x47bdb1): Section mismatch in reference from the function pci_scan_child_bus() to the function .devinit.text:pcibios_fixup_bus()

We had plenty of functions that could be annotated __devinit but due to
the former restriction that exported symbols could not be annotated
they were not so.  So annotate these function and fix the references
from the pci/hotplug/* code to silence the resuting warnings.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-04 15:07:03 -08:00
Kenji Kaneshige
2326e2b999 pciehp: block new requests from the device before power off
Disable Bus Master, SERR# and INTx to ensure that no new Requests will
be generated from the device before turning power off, in accordance
with the specification.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:28 -08:00
Rolf Eike Beer
f07234b66a PCI Hotplug: PCIeHP: Fix some whitespace damage
PCIeHP: Fix some whitespace damage

Signed-off-by: Rolf Eike Beer <eike-hotplug@sf-tec.de>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:24 -08:00
Kenji Kaneshige
9515930ea2 PCI Hotplug: pciehp: use generic function to find ext capability
Remove duplicated code to find an extend capability in PCIEHP driver.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:24 -08:00
Kenji Kaneshige
9fe8164536 pciehp: remove trailing whitespace form pciehp_pci.c
Remove trailing whitespaces from pciehp_pci.c.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 15:03:14 -07:00
Kristen Carlson Accardi
1cf53d5ddb PCI Hotplug: pciehp: Dont check bridge control on remove
When removing a device with a bridge on it, only read the
bridge control register if the adapter is actually present.

Signed-off-by:  Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 15:03:14 -07:00
Kenji Kaneshige
6e33706b19 [PATCH] pciehp: Add missing pci_dev_put
The PCIEHP driver leaks reference counter of pci_dev structures. This
patch adds missing pci_dev_put() calls to PCIEHP driver.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-19 14:13:23 -07:00
Kenji Kaneshige
56bfada3e1 [PATCH] pciehp: Replace pci_find_slot() with pci_get_slot()
This patch replaces pci_find_slot() with pci_get_slot() in PCIEHP
driver. This patch enables PCI Express Hotplug on the system which has
multiple PCI domains.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-19 14:13:23 -07:00
Kenji Kaneshige
40abb96c51 [PATCH] pciehp: Fix programming hotplug parameters
Current PCHEHP driver doesn't have any code to program hotplug
parameters from firmware. So hotplug parameters are never programed at
hot-add time. This patch add support for programming hotplug
parameters to PCIEHP driver.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-19 14:13:22 -07:00
Rajesh Shah
0eb3bcfd08 [PATCH] pciehp: allow bridged card hotplug
This patch fixes bugs in the pciehp driver that prevent hot-add
of a card with PCI bridges on it.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-09 12:13:18 -08:00
rajesh.shah@intel.com
ed6cbcf2ac [PATCH] pciehp: miscellaneous cleanups
Remove un-necessary header includes, remove dead code, remove
some hardcoded constants...

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-10 16:09:15 -08:00
rajesh.shah@intel.com
ca22a5e4d7 [PATCH] pciehp: remove redundant data structures
State information is currently stored in per-slot as well as
per-pci-function data structures in pciehp. There's a lot of
overlap in the information kept, and some of it is never used.
This patch consolidates the state information to per-slot and
eliminates unused data structures. The biggest change is to
eliminate the pci_func structure and the code around managing
its lists.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-10 16:09:14 -08:00