Commit Graph

107 Commits

Author SHA1 Message Date
Lukas Wunner 281e878eab PCI: pciehp: Fix use-after-free on unplug
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
2018-07-23 17:04:10 -05:00
Mika Westerberg 13c65840fe PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
After a suspend/resume cycle the Presence Detect or Data Link Layer Status
Changed bits might be set.  If we don't clear them those events will not
fire anymore and nothing happens for instance when a device is now
hot-unplugged.

Fix this by clearing those bits in a newly introduced function
pcie_reenable_notification().  This should be fine because immediately
after, we check if the adapter is still present by reading directly from
the status register.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org
2018-05-23 17:42:53 -05:00
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
Bjorn Helgaas 5fbeef6377 PCI: pciehp: Remove loading message
Remove the "PCI Express Hot Plug Controller Driver" version message.  I
don't think it contains any useful information.  Remove unused #defines
and move the author information to a comment.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-12-12 10:05:24 -06:00
Bjorn Helgaas 64ea3b99d6 Merge branch 'pci/hotplug' into next
* pci/hotplug:
  x86/PCI: VMD: Request userspace control of PCIe hotplug indicators
  PCI: pciehp: Allow exclusive userspace control of indicators
  PCI: pciehp: Remove useless pciehp_get_latch_status() calls
  PCI: pciehp: Clean up dmesg "Slot(%s)" messages
  PCI: pciehp: Remove unnecessary guard
  PCI: pciehp: Don't re-read Slot Status when handling surprise event
  PCI: pciehp: Don't re-read Slot Status when queuing hotplug event
  PCI: pciehp: Process all hotplug events before looking for new ones
  PCI: pciehp: Return IRQ_NONE when we can't read interrupt status
  PCI: pciehp: Rename pcie_isr() locals for clarity
  PCI: pciehp: Clear attention LED on device add
2016-10-03 09:43:19 -05:00
Keith Busch 576243b3f9 PCI: pciehp: Allow exclusive userspace control of indicators
PCIe hotplug supports optional Attention and Power Indicators, which are
used internally by pciehp.  Users can't control the Power Indicator, but
they can control the Attention Indicator by writing to a sysfs "attention"
file.

The Slot Control register has two bits for each indicator, and the PCIe
spec defines the encodings for each as (Reserved/On/Blinking/Off).  For
sysfs "attention" writes, pciehp_set_attention_status() maps into these
encodings, so the only useful write values are 0 (Off), 1 (On), and 2
(Blinking).

However, some platforms use all four bits for platform-specific indicators,
and they need to allow direct user control of them while preventing pciehp
from using them at all.

Add a "hotplug_user_indicators" flag to the pci_dev structure.  When set,
pciehp does not use either the Attention Indicator or the Power Indicator,
and the low four bits (values 0x0 - 0xf) of sysfs "attention" write values
are written directly to the Attention Indicator Control and Power Indicator
Control fields.

[bhelgaas: changelog, rename flag and accessors to s/attention/indicator/]
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-09-22 18:20:11 -05:00
Paul Gortmaker 70626d8838 PCI: pciehp: Make explicitly non-modular
This code is not being built as a module by anyone:

  obj-$(CONFIG_HOTPLUG_PCI_PCIE)          += pciehp.o
  pciehp-objs                             := pciehp_core.o   \

  drivers/pci/pcie/Kconfig:config HOTPLUG_PCI_PCIE
  drivers/pci/pcie/Kconfig:  bool "PCI Express Hotplug driver"

Remove uses of MODULE_DESCRIPTION(), MODULE_AUTHOR(), MODULE_LICENSE(),
etc., so that when reading the driver there is no doubt it is builtin-only.
The information is preserved in comments at the top of the file.

Note that for non-modular code, module_init() translates to
device_initcall().  One could argue that we should use subsys_initcall()
here, but for now we stick with runtime equivalence.

We delete module.h but we keep the moduleparam.h include, since we are
keeping the module_param() that the file has as-is for now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Kristen Carlson Accardi <kristen@linux.intel.com>
2016-08-24 17:28:56 -05:00
Bogicevic Sasa ff3ce480e8 PCI: Fix all whitespace issues
Fix all whitespace issues (missing or needed whitespace) in all files in
drivers/pci.  Code is compiled with allyesconfig before and after code
changes and objects are recorded and checked with objdiff and they are not
changed after this commit.

Signed-off-by: Bogicevic Sasa <brutallesale@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-01-08 10:35:24 -06:00
Bjorn Helgaas 3784e0c6b0 PCI: pciehp: Clean up debug logging
The pciehp debug logging is overly verbose and often redundant.  Almost all
of the information printed by dbg_ctrl() is also printed by the normal PCI
core enumeration code and by pcie_init().

Remove the redundant debug info.

When claiming a pciehp bridge, we print the slot characteristics, e.g.,

  Slot #6 AttnBtn- AttnInd- PwrInd- PwrCtrl- MRL- Interlock- NoCompl+ LLActRep+

Add the Hot-Plug Capable and Hot-Plug Surprise bits to this information,
and print it all in the same order as lspci does.

No functional change except the message text changes.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rajat Jain <rajatja@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
2015-06-17 17:35:28 -05:00
Rafael J. Wysocki 2af31f415f PCI: pciehp: Drop pointless label from pciehp_probe()
The err_out_none label in pciehp_probe() only leads to a return statement,
so use return statements instead of jumps to it and drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-22 17:38:47 -05:00
Rafael J. Wysocki e705c2959b PCI: pciehp: Drop pointless ACPI-based "slot detection" check
Jarod Wilson reports that ExpressCard hotplug doesn't work on HP ZBook G2.
The problem turns out to be the ACPI-based "slot detection" code called
from pciehp_probe() which uses questionable heuristics based on what ACPI
objects are present for the PCIe port device to figure out whether to
register a hotplug slot for that port.

That code is used if there is at least one PCIe port having an ACPI device
configuration object related to hotplug (such as _EJ0 or _RMV), and the
Thunderbolt port on the ZBook has _RMV.  Of course, Thunderbolt and PCIe
native hotplug need not be mutually exclusive (as they aren't on the
ZBook), so that rule is simply incorrect.

Moreover, the ACPI-based "slot detection" check does not add any value if
pciehp_probe() is called at all and the service type of the device object
it has been called for is PCIE_PORT_SERVICE_HP, because PCIe hotplug
services are only registered if the _OSC handshake in acpi_pci_root_add()
allows the kernel to control the PCIe native hotplug feature.  No more
checks need to be carried out to decide whether or not to register a native
PCIe hotlug slot in that case.

For the above reasons, make pciehp_probe() check if it has been called for
the right service type and drop the pointless ACPI-based "slot detection"
check from it.  Also remove the entire code whose only user is that check
(the entire pciehp_acpi.c file goes away as a result) and drop function
headers related to it from the internal pciehp header file.

Link: http://lkml.kernel.org/r/1431632038-39917-1-git-send-email-jarod@redhat.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=98581
Reported-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jarod Wilson <jarod@redhat.com>
Tested-by: Jarod Wilson <jarod@redhat.com>
2015-05-21 11:01:12 -05:00
Kamal Mostafa c302d35eac Revert duplicate "PCI: pciehp: Prevent NULL dereference during probe"
This reverts bceee4a97e ("PCI: pciehp: Prevent NULL dereference during
probe") because it was accidentally applied twice:

  62e4492c30 ("PCI: Prevent NULL dereference during pciehp probe")
  bceee4a97e ("PCI: pciehp: Prevent NULL dereference during probe")

Revert the latter to dispose of the duplicated code block.

[bhelgaas: tidy changelog, drop stable tag]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Andreas Noever <andreas.noever@gmail.com>
2014-10-27 11:42:43 -06:00
Andreas Noever bceee4a97e PCI: pciehp: Prevent NULL dereference during probe
pciehp assumes that dev->subordinate, the struct pci_bus for a bridge's
secondary bus, exists.  But we do not create that bus if we run out of bus
numbers during enumeration.  This leads to a NULL dereference in
init_slot() (and other places).

Change pciehp_probe() to return -ENODEV when no secondary bus is present.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.2+
2014-09-16 15:16:02 -06:00
Andreas Noever 62e4492c30 PCI: Prevent NULL dereference during pciehp probe
pciehp assumes that dev->subordinate exists.  But we do not assign a bus if
we run out of bus numbers during enumeration.  This leads to a NULL
dereference in init_slot() (and other places).

Change pciehp_probe() to return -ENODEV when no subordinate bus is present.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-16 11:47:37 -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
Ryan Desfosses 3c78bc61f5 PCI: Whitespace cleanup
Fix various whitespace errors.

No functional change.

[bhelgaas: fix other similar problems]
Signed-off-by: Ryan Desfosses <ryan@desfo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-10 20:20:19 -06:00
Bjorn Helgaas 9cad7f5820 PCI: pciehp: Cleanup whitespace
Minor whitespace cleanup; no functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-19 15:05:25 -07:00
Rajat Jain 50b52fdee0 PCI: pciehp: Add hotplug_lock to serialize hotplug events
Today it is there is no protection around pciehp_enable_slot() and
pciehp_disable_slot() to ensure that they complete before another
hot-plug operation can be done on that particular slot.

This patch introduces the slot->hotplug_lock to ensure that any hotplug
operations (add / remove) complete before another hotplug event can begin
processing on that particular slot.

Signed-off-by: Rajat Jain <rajatxjain@gmail.com>
Signed-off-by: Rajat Jain <rajatjain@juniper.net>
Signed-off-by: Guenter Roeck <groeck@juniper.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-11 16:13:16 -07:00
Bjorn Helgaas 597db6f38c Merge branch 'pci/dead-code' into next
* pci/dead-code:
  PCI: Make local functions static
  PCI: Remove unused alloc_pci_dev()
  PCI: Remove unused pci_renumber_slot()
  PCI: Remove unused pcie_aspm_enabled()
  PCI: Remove unused pci_vpd_truncate()
  PCI: Remove unused ID-Based Ordering support
  PCI: Remove unused Optimized Buffer Flush/Fill support
  PCI: Remove unused Latency Tolerance Reporting support
  PCI: Removed unused parts of Page Request Interface support

Conflicts:
	drivers/pci/pci.c
	include/linux/pci.h
2014-01-13 16:47:08 -07:00
Stephen Hemminger 0b950f0f3c PCI: Make local functions static
Using 'make namespacecheck' identify code which should be declared static.
Checked for users in other driver/archs as well.  Compile tested only.

This stops exporting the following interfaces to modules:

    pci_target_state()
    pci_load_saved_state()

[bhelgaas: retained pci_find_next_ext_capability() and pci_cfg_space_size()]
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-13 11:57:29 -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
Bjorn Helgaas f7625980f5 PCI: Fix whitespace, capitalization, and spelling errors
Fix whitespace, capitalization, and spelling errors.  No functional change.
I know "busses" is not an error, but "buses" was more common, so I used it
consistently.

Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus())
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14 11:28:18 -07:00
Alex Williamson 2e35afaefe PCI: pciehp: Add reset_slot() method
PCIe hotplug has a bus per slot, so we can just use a normal
secondary bus reset.  However, if a slot supports surprise removal,
a bus reset can be seen as a presence detection change triggering
a hot-remove followed by a hot-add.  Disable presence detection from
triggering an interrupt or being polled around the bus reset.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-08-14 14:55:26 -06:00
Linus Torvalds 556f12f602 PCI changes for the v3.9 merge window:
Host bridge hotplug
     - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
     - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
     - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
     - Stop caching _PRT and make independent of bus numbers (Yinghai Lu)
 
   PCI device hotplug
     - Clean up cpqphp dead code (Sasha Levin)
     - Disable ARI unless device and upstream bridge support it (Yijing Wang)
     - Initialize all hot-added devices (not functions 0-7) (Yijing Wang)
 
   Power management
     - Don't touch ASPM if disabled (Joe Lawrence)
     - Fix ASPM link state management (Myron Stowe)
 
   Miscellaneous
     - Fix PCI_EXP_FLAGS accessor (Alex Williamson)
     - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
     - Document hotplug resource and MPS parameters (Yijing Wang)
     - Add accessor for PCIe capabilities (Myron Stowe)
     - Drop pciehp suspend/resume messages (Paul Bolle)
     - Make pci_slot built-in only (not a module) (Jiang Liu)
     - Remove unused PCI/ACPI bind ops (Jiang Liu)
     - Removed used pci_root_bus (Bjorn Helgaas)
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Merge tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI changes from Bjorn Helgaas:
 "Host bridge hotplug
    - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
    - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
    - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
    - Stop caching _PRT and make independent of bus numbers (Yinghai Lu)

  PCI device hotplug
    - Clean up cpqphp dead code (Sasha Levin)
    - Disable ARI unless device and upstream bridge support it (Yijing Wang)
    - Initialize all hot-added devices (not functions 0-7) (Yijing Wang)

  Power management
    - Don't touch ASPM if disabled (Joe Lawrence)
    - Fix ASPM link state management (Myron Stowe)

  Miscellaneous
    - Fix PCI_EXP_FLAGS accessor (Alex Williamson)
    - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
    - Document hotplug resource and MPS parameters (Yijing Wang)
    - Add accessor for PCIe capabilities (Myron Stowe)
    - Drop pciehp suspend/resume messages (Paul Bolle)
    - Make pci_slot built-in only (not a module) (Jiang Liu)
    - Remove unused PCI/ACPI bind ops (Jiang Liu)
    - Removed used pci_root_bus (Bjorn Helgaas)"

* tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits)
  PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers
  PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS
  ACPI / PCI: Make pci_slot built-in only, not a module
  PCI/PM: Clear state_saved during suspend
  PCI: Use atomic_inc_return() rather than atomic_add_return()
  PCI: Catch attempts to disable already-disabled devices
  PCI: Disable Bus Master unconditionally in pci_device_shutdown()
  PCI: acpiphp: Remove dead code for PCI host bridge hotplug
  PCI: acpiphp: Create companion ACPI devices before creating PCI devices
  PCI: Remove unused "rc" in virtfn_add_bus()
  PCI: pciehp: Drop suspend/resume ENTRY messages
  PCI/ASPM: Don't touch ASPM if forcibly disabled
  PCI/ASPM: Deallocate upstream link state even if device is not PCIe
  PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc
  PCI: Document hpiosize= and hpmemsize= resource reservation parameters
  PCI: Use PCI Express Capability accessor
  PCI: Introduce accessor to retrieve PCIe Capabilities Register
  PCI: Put pci_dev in device tree as early as possible
  PCI: Skip attaching driver in device_add()
  PCI: acpiphp: Keep driver loaded even if no slots found
  ...
2013-02-25 21:18:18 -08:00
Paul Bolle 775c739e0b PCI: pciehp: Drop suspend/resume ENTRY messages
In each suspend and resume cycle my laptop prints these messages at
KERN_INFO level:
    pciehp 0000:00:1c.1:pcie04: pciehp_suspend ENTRY
    pciehp 0000:00:1c.0:pcie04: pciehp_suspend ENTRY

and
    pciehp 0000:00:1c.0:pcie04: pciehp_resume ENTRY
    pciehp 0000:00:1c.1:pcie04: pciehp_resume ENTRY

Drop these messages, that were probably used to debug the suspend and
resume code, but now serve no purpose.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-02-01 15:56:05 -07:00
Yijing Wang c2be6f93b3 PCI: pciehp: Use per-slot workqueues to avoid deadlock
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.

The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port.  When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method.  That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  pciehp_queue_pushbutton_work
    queue_work(pciehp_wq)                   # queue pciehp_power_thread
    ...

  pciehp_power_thread
    pciehp_disable_slot
      remove_board
	pciehp_unconfigure_device
	  pci_stop_and_remove_bus_device
	    ...
	      pciehp_remove                 # pciehp driver .remove method
		pciehp_release_ctrl
		  pcie_cleanup_slot
		    flush_workqueue(pciehp_wq)

This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.

[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
2013-01-12 13:56:33 -07:00
Oliver Neukum 87683e22c6 PCI: pciehp: Always implement resume, regardless of pciehp_force param
Previously, the driver ignored resume unless the pciehp_force module_param
was specified.  On some laptops that means that interrupts are not
delivered after S3, so card removals and insertions are not handled.
This patch makes the driver handle resume regardless of pciehp_force.

[bhelgaas: changelog]
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-07 17:06:54 -06:00
Rusty Russell 90ab5ee941 module_param: make bool parameters really bool (drivers & misc)
module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:20 +10:30
Kenji Kaneshige 486b10b9f4 PCI: pciehp: Handle push button event asynchronously
Use non-ordered workqueue for attention button events.

Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in pciehp as a result.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-12-05 10:21:47 -08:00
Kenji Kaneshige 027e8d52ab PCI: pciehp: Fix wrong workqueue cleanup
Fix improper workqueue cleanup.

In the current pciehp, pcied_cleanup() calls destroy_workqueue()
before calling pcie_port_service_unregister(). This causes kernel oops
because flush_workqueue() is called in the pcie_port_service_unregister()
code path after the workqueue was destroyed. So pcied_cleanup() must call
pcie_port_service_unregister() first before calling destroy_workqueue().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-12-05 10:21:46 -08:00
Tejun Heo a827ea307b pciehp: update workqueue usage
* Rename pciehp_wq to pciehp_ordered_wq and add non-ordered pciehp_wq
  which is used instead of the system workqueue.  This is to remove
  the use of flush_scheduled_work() which is deprecated and scheduled
  for removal.

* With cmwq in place, there's no point in creating workqueues lazily.
  Create both pciehp_wq and pciehp_ordered_wq upfront.

* Include workqueue.h from pciehp.h.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-10-18 08:31:02 +02:00
Rafael J. Wysocki 28eb5f274a PCI: PCIe: Ask BIOS for control of all native services at once
After commit 852972acff (ACPI: Disable
ASPM if the platform won't provide _OSC control for PCIe) control of
the PCIe Capability Structure is unconditionally requested by
acpi_pci_root_add(), which in principle may cause problems to
happen in two ways.  First, the BIOS may refuse to give control of
the PCIe Capability Structure if it is not asked for any of the
_OSC features depending on it at the same time.  Second, the BIOS may
assume that control of the _OSC features depending on the PCIe
Capability Structure will be requested in the future and may behave
incorrectly if that doesn't happen.  For this reason, control of
the PCIe Capability Structure should always be requested along with
control of any other _OSC features that may depend on it (ie. PCIe
native PME, PCIe native hot-plug, PCIe AER).

Rework the PCIe port driver so that (1) it checks which native PCIe
port services can be enabled, according to the BIOS, and (2) it
requests control of all these services simultaneously.  In
particular, this causes pcie_portdrv_probe() to fail if the BIOS
refuses to grant control of the PCIe Capability Structure, which
means that no native PCIe port services can be enabled for the PCIe
Root Complex the given port belongs to.  If that happens, ASPM is
disabled to avoid problems with mishandling it by the part of the
PCIe hierarchy for which control of the PCIe Capability Structure
has not been received.

Make it possible to override this behavior using 'pcie_ports=native'
(use the PCIe native services regardless of the BIOS response to the
control request), or 'pcie_ports=compat' (do not use the PCIe native
services at all).

Accordingly, rework the existing PCIe port service drivers so that
they don't request control of the services directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-24 13:47:33 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Matthew Wilcox 3749c51ac6 PCI: Make current and maximum bus speeds part of the PCI core
Move the max_bus_speed and cur_bus_speed into the pci_bus.  Expose the
values through the PCI slot driver instead of the hotplug slot driver.
Update all the hotplug drivers to use the pci_bus instead of their own
data structures.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22 16:15:17 -08:00
Kenji Kaneshige 8792e11f1c PCI: pciehp: prevent unnecessary power off
Prevent unnecessary power off at initialization time. If slot power
is already off, we don't need to power off the slot.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:02:35 -08:00
Kenji Kaneshige 65b947bc5f PCI: pciehp: fix typo in pciehp_probe
Fix typo that might cause memory leak in pciehp_probe().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:02:13 -08:00
Kenji Kaneshige 445f798555 PCI: pciehp: return error on read/write failure
Current pciehp returns successfully on read/write failure with dummy
state values. It should return error instead.

With this patch, pciehp no longer uses hotplug_slot_info data
structure. So this also removes hotplug_slot_info related code. But
note that it still allocates hotplug_slot_info because it is required
by pci hotplug core.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:01:59 -08:00
Kenji Kaneshige 586f1d6688 PCI: pciehp: create files only for existing capabilities
Current pciehp driver creates 'attention' and 'latch' files even if
the controller doesn't support them. In this case, the contents of
those files are meaningless and unpredictable. Those files should be
created only if the controller has the corresponding capabilities.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 09:01:44 -08:00
Kenji Kaneshige 07a09694de PCI: pciehp: remove number field
Since slot_cap field in struct controller contains physical slot
number informationq, we don't need number field in struct slot.

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 10:06:36 -07:00
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 a2359a334f PCI: pciehp: remove slot_device_offset field
Since the device number of the hot-slot under the PCIe downstream port
is always 0, the slot_device_offset field in the slot is meaningless
and we don't need it.

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 10:06:02 -07:00
Kenji Kaneshige 0e3631593c PCI: pciehp: remove hp_slot field
The hp_slot field is to identify the slot under the same
controller. But, since PCIe downstream port has only one slot at most,
it is meaningless and we don't need it.

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 10:05:58 -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
Kenji Kaneshige 8720d27dab PCI: pciehp: remove slot_list field
Since PCIe downstream port has only one slot at most, we don't need
'slot_list' linked list to manage multiple slots under the port.

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 10:05:31 -07:00
Kenji Kaneshige a6c0d5c6eb PCI hotplug: remove redundant .owner initializations
The "owner" field in struct hotplug_slot_ops is initialized by PCI
hotplug core. So each hotplug controller driver doesn't need to
initialize it.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:12 -07:00
Kenji Kaneshige bd3d99c170 PCI: Remove untested Electromechanical Interlock (EMI) support in pciehp.
The EMI support in pciehp is obviously broken. It is implemented using
struct hotplug_slot_attribute, but sysfs_ops for pci_slot_ktype is NOT
for struct hotplug_slot_attribute, but for struct pci_slot_attribute.
This bug had been there for a long time, maybe it was introduced when
PCI slot framework was introduced. The reason why this bug didn't
cause any problem is maybe the EMI support is not tested at all
because of lack of test environment.

As described above, the EMI support in pciehp seems not to be tested
at all. So this patch removes EMI support from pciehp, instead of
fixing the bug.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:10 -07:00
Rafael J. Wysocki 3a3c244c9a PCI: PCIe portdrv: Implement pm object
Implement pm object for the PCI Express port driver in order to use
the new power management framework and reduce the code size.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:47:49 -07:00
Rafael J. Wysocki 22106368c9 PCI: PCIe portdrv: Remove struct pcie_port_service_id
The PCI Express port driver uses 'struct pcie_port_service_id' for
matching port service devices and drivers, but this structure
contains fields that duplicate information from the port device
itself (vendor, device, subvendor, subdevice) and fields that are not
used by any existing port service driver (class, class_mask,
drvier_data).  Also, both existing port service drivers (AER and
PCIe HP) don't even use the vendor and device fields for device
matching.  Therefore 'struct pcie_port_service_id' can be removed
altogether and the only useful members of it (port_type, service) can
be introduced directly into the port service device and port service
driver structures.  That simplifies the code quite a bit and reduces
its size.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19 19:29:23 -07:00