The interactions between the ACPI dock driver and the ACPI-based PCI
hotplug (acpiphp) are currently problematic because of ordering
issues during hot-remove operations.
First of all, the current ACPI glue code expects that physical
devices will always be deleted before deleting the companion ACPI
device objects. Otherwise, acpi_unbind_one() will fail with a
warning message printed to the kernel log, for example:
[ 185.026073] usb usb5: Oops, 'acpi_handle' corrupt
[ 185.035150] pci 0000:1b:00.0: Oops, 'acpi_handle' corrupt
[ 185.035515] pci 0000:18:02.0: Oops, 'acpi_handle' corrupt
[ 180.013656] port1: Oops, 'acpi_handle' corrupt
This means, in particular, that struct pci_dev objects have to
be deleted before the struct acpi_device objects they are "glued"
with.
Now, the following happens the during the undocking of an ACPI-based
dock station:
1) hotplug_dock_devices() invokes registered hotplug callbacks to
destroy physical devices associated with the ACPI device objects
depending on the dock station. It calls dd->ops->handler() for
each of those device objects.
2) For PCI devices dd->ops->handler() points to
handle_hotplug_event_func() that queues up a separate work item
to execute _handle_hotplug_event_func() for the given device and
returns immediately. That work item will be executed later.
3) hotplug_dock_devices() calls dock_remove_acpi_device() for each
device depending on the dock station. This runs acpi_bus_trim()
for each of them, which causes the underlying ACPI device object
to be destroyed, but the work items queued up by
handle_hotplug_event_func() haven't been started yet.
4) _handle_hotplug_event_func() queued up in step 2) are executed
and cause the above failure to happen, because the PCI devices
they handle do not have the companion ACPI device objects any
more (those objects have been deleted in step 3).
The possible breakage doesn't end here, though, because
hotplug_dock_devices() may return before at least some of the
_handle_hotplug_event_func() work items spawned by it have a
chance to complete and then undock() will cause _DCK to be
evaluated and that will cause the devices handled by the
_handle_hotplug_event_func() to go away possibly while they are
being accessed.
This means that dd->ops->handler() for PCI devices should not point
to handle_hotplug_event_func(). Instead, it should point to a
function that will do the work of _handle_hotplug_event_func()
synchronously. For this reason, introduce such a function,
hotplug_event_func(), and modity acpiphp_dock_ops to point to
it as the handler.
Unfortunately, however, this is not sufficient, because if the dock
code were not changed further, hotplug_event_func() would now
deadlock with hotplug_dock_devices() that called it, since it would
run unregister_hotplug_dock_device() which in turn would attempt to
acquire the dock station's hp_lock mutex already acquired by
hotplug_dock_devices().
To resolve that deadlock use the observation that
unregister_hotplug_dock_device() won't need to acquire hp_lock
if PCI bridges the devices on the dock station depend on are
prevented from being removed prematurely while the first loop in
hotplug_dock_devices() is in progress.
To make that possible, introduce a mechanism by which the callers of
register_hotplug_dock_device() can provide "init" and "release"
routines that will be executed, respectively, during the addition
and removal of the physical device object associated with the
given ACPI device handle. Make acpiphp use two new functions,
acpiphp_dock_init() and acpiphp_dock_release(), that call
get_bridge() and put_bridge(), respectively, on the acpiphp bridge
holding the given device, for this purpose.
In addition to that, remove the dock station's list of
"hotplug devices" and make the dock code always walk the whole list
of "dependent devices" instead in such a way that the loops in
hotplug_dock_devices() and dock_event() (replacing the loops over
"hotplug devices") will take references to the list entries that
register_hotplug_dock_device() has been called for. That prevents
the "release" routines associated with those entries from being
called while the given entry is being processed and for PCI
devices this means that their bridges won't be removed (by a
concurrent thread) while hotplug_event_func() handling them is
being executed.
This change is based on two earlier patches from Jiang Liu.
References: https://bugzilla.kernel.org/show_bug.cgi?id=59501
Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com>
Tracked-down-by: Jiang Liu <jiang.liu@huawei.com>
Tested-by: Illya Klymov <xanf@xanf.me>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: 3.9+ <stable@vger.kernel.org>
On x86 platforms, the kernel respects PCI resource assignments from
the BIOS and only reassigns resources for unassigned BARs at boot
time. However, with the ACPI-based hotplug (acpiphp), it ignores the
BIOS' PCI resource assignments completely and reassigns all resources
by itself. This causes differences in PCI resource allocation
between boot time and runtime hotplug to occur, which is generally
undesirable and sometimes actively breaks things.
Namely, if there are enough resources, reassigning all PCI resources
during runtime hotplug should work, but it may fail if the resources
are constrained. This may happen, for instance, when some PCI
devices with huge MMIO BARs are involved in the runtime hotplug
operations, because the current PCI MMIO alignment algorithm may
waste huge chunks of MMIO address space in those cases.
On the Alexander's Sony VAIO VPCZ23A4R the BIOS allocates limited
MMIO resources for the dock station which contains a device
(graphics adapter) with a 256MB MMIO BAR. An attempt to reassign
that during runtime hotplug causes the dock station MMIO window to be
exhausted and acpiphp fails to allocate resources for the majority
of devices on the dock station as a result.
To prevent that from happening, modify acpiphp to follow the boot
time resources allocation behavior so that the BIOS' resource
assignments are respected during runtime hotplug too.
[rjw: Changelog]
References: https://bugzilla.kernel.org/show_bug.cgi?id=56531
Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com>
Tested-by: Illya Klymov <xanf@xanf.me>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When a PCI host bridge device receives a Bus Check notification, we
must re-enumerate starting with the bridge to discover changes (devices
that have been added or removed).
Prior to 668192b678 ("PCI: acpiphp: Move host bridge hotplug to
pci_root.c"), this happened in _handle_hotplug_event_bridge(). After that
commit, _handle_hotplug_event_bridge() is not installed for host bridges,
and the host bridge notify handler, _handle_hotplug_event_root() did not
re-enumerate.
This patch adds re-enumeration to _handle_hotplug_event_root().
This fixes cases where we don't notice the addition or removal of
PCI devices, e.g., the PCI-to-USB ExpressCard in the bugzilla below.
[bhelgaas: changelog, references]
Reference: https://lkml.kernel.org/r/CAAh6nkmbKR3HTqm5ommevsBwhL_u0N8Rk7Wsms_LfP=nBgKNew@mail.gmail.com
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=57961
Reported-by: Gavin Guo <tuffkidtt@gmail.com>
Tested-by: Gavin Guo <tuffkidtt@gmail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org # v3.9+
* pci/cleanup:
PCI: Remove "extern" from function declarations
PCI: Warn about failures instead of "must_check" functions
PCI: Remove __must_check from definitions
PCI: Remove unused variables
PCI: Move cpci_hotplug_init() proto to header file
PCI: Make local functions/structs static
PCI: Fix missing prototype for pcie_port_acpi_setup()
Conflicts:
drivers/pci/hotplug/acpiphp.h
include/linux/pci.h
We had an inconsistent mix of using and omitting the "extern" keyword
on function declarations in header files. This removes them all.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The __must_check (gcc "warn_unused_result") attribute only makes sense
when compiling the *caller* of the function, so the attribute should
appear on the declaration in the header file, not on the definition.
The declarations of these functions are already annotated with
__must_check.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Don't modify function handles to get a disabled handle - call
clp_disable_fh. With this change we also do no longer deconfigure
enabled functions.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the debugfs to keep track of a pci function's status changes.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* pci/jiang-subdrivers:
PCI/ACPI: Remove support of ACPI PCI subdrivers
PCI: acpiphp: Protect acpiphp data structures from concurrent updates
PCI: acpiphp: Use normal list to simplify implementation
PCI: acpiphp: Do not use ACPI PCI subdriver mechanism
PCI: acpiphp: Convert acpiphp to be builtin only, not modular
PCI/ACPI: Handle PCI slot devices when creating/destroying PCI buses
x86/PCI: Implement pcibios_{add|remove}_bus() hooks
ia64/PCI: Implement pcibios_{add|remove}_bus() hooks
PCI/ACPI: Prepare stub functions to handle ACPI PCI (hotplug) slots
PCI: Add pcibios hooks for adding and removing PCI buses
PCI: acpiphp: Replace local macros with standard ACPI macros
PCI: acpiphp: Remove all functions even if function 0 doesn't exist
PCI: acpiphp: Use list_for_each_entry_safe() in acpiphp_sanitize_bus()
PCI: Clean up usages of pci_bus->is_added
PCI: When removing bus, always remove legacy files & unregister
Now acpiphp_enumerate_slots() and acpiphp_remove_slots() may be invoked
concurrently by the PCI core, so add a bridge_mutex and reference count
mechanism to protect acpiphp bridge/slot/function data structures.
To avoid deadlock, handle_hotplug_event_bridge() will requeue the
hotplug event onto the kacpi_hotplug_wq by calling alloc_acpi_hp_work().
But the workaround has introduced a minor race window because the
'bridge' passed to _handle_hotplug_event_bridge() may have already been
destroyed when _handle_hotplug_event_bridge() is actually executed by
the kacpi_hotplug_wq. So hold a reference count on the passed 'bridge'.
Fix the same issue for handle_hotplug_event_func() too.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Use normal list for struct acpiphp_slot to simplify implementation.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Use PCI_EXP_SLTCAP_PSN mask to make it easier to find where the
Physical Slot Number is used.
The Physical Slot Number is bits 31:19 of the Slot Capabilities Register,
and slot_cap is a u32, so the mask is technically unnecessary, but it's
helpful for human readers.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
cpci_hotplug_init() and cpci_hotplug_exit() are defined in
cpci_hotplug_core.c but had extern declarations in pci_hotplug_core.c.
This puts the declarations in a header file included both places so
the compiler can help keep everything consistent.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously the acpiphp driver registered itself as an ACPI PCI subdriver,
so its callbacks were invoked when creating/destroying PCI root
buses to manage ACPI-based PCI hotplug slots. But it doesn't handle
P2P bridge hotplug events, so it will cause strange behaviour if there
are hotplug slots associated with a hot-removed P2P bridge.
This patch fixes this issue by:
1) Directly hooking into PCI core to update hotplug slot devices when
creating/destroying PCI buses through:
pci_{add|remove}_bus() -> acpi_pci_{add|remove}_bus()
2) Getting rid of unused ACPI PCI subdriver-related code
It also cleans up unused code in the acpiphp driver.
[bhelgaas: keep acpi_pci_add_bus() stub for CONFIG_ACPI=n]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Convert acpiphp to be builtin only, with no module option.
Previously, when HOTPLUG_PCI_ACPI=m, users could disable acpiphp by
removing the module or preventing it from loading. That can't be done
if acpiphp is builtin statically, so this adds an "acpiphp.disable"
kernel parameter. If a user needs to use this parameter, it is a bug,
and we want to hear about it.
[bhelgaas: fold in acpiphp.disable here, remove documentation]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Replace local defined macros (ACPI_STA_xxx) with standard ACPI macros
(ACPI_STA_DEVICE_xxx).
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Currently function disable_device() detects slot state by checking
existence of PCI function 0. It's unreliable because the PCI device
for function 0 may be removed through the sysfs interface. If that
happens, it will cause powering off a hotplug slot without destroying
all PCI devices.
On the other hand, it won't hurt us except wasting some computation
power if the check is removed, because all code of disable_device()
is self-protected. So remove the check.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Function acpiphp_sanitize_bus() may call pci_stop_and_remove_bus_device(),
which in turn may remove device from bus->devices list. So walk the
bus->devices list with list_for_each_entry_safe().
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
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
...
Pull s390 update from Martin Schwidefsky:
"The most prominent change in this patch set is the software dirty bit
patch for s390. It removes __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY and
the page_test_and_clear_dirty primitive which makes the common memory
management code a bit less obscure.
Heiko fixed most of the PCI related fallout, more often than not
missing GENERIC_HARDIRQS dependencies. Notable is one of the 3270
patches which adds an export to tty_io to be able to resize a tty.
The rest is the usual bunch of cleanups and bug fixes."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/module: Add missing R_390_NONE relocation type
drivers/gpio: add missing GENERIC_HARDIRQ dependency
drivers/input: add couple of missing GENERIC_HARDIRQS dependencies
s390/cleanup: rename SPP to LPP
s390/mm: implement software dirty bits
s390/mm: Fix crst upgrade of mmap with MAP_FIXED
s390/linker skript: discard exit.data at runtime
drivers/media: add missing GENERIC_HARDIRQS dependency
s390/bpf,jit: add vlan tag support
drivers/net,AT91RM9200: add missing GENERIC_HARDIRQS dependency
iucv: fix kernel panic at reboot
s390/Kconfig: sort list of arch selected config options
phylib: remove !S390 dependeny from Kconfig
uio: remove !S390 dependency from Kconfig
dasd: fix sysfs cleanup in dasd_generic_remove
s390/pci: fix hotplug module init
s390/pci: cleanup clp page allocation
s390/pci: cleanup clp inline assembly
s390/perf: cpum_cf: fallback to software sampling events
s390/mm: provide PAGE_SHARED define
...
Loading the pci hotplug module when no devices are present will fail
but unfortunately some hotplug callbacks stay registered to the pci
bus level. Fix this by not letting module loading fail when no pci
devices are present and provide proper {de}registration functions
for these callbacks.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
pci_probe is too generic and has a name clash with other common code parts.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This changeset is aimed at fixing a few different but related
problems in the ACPI hotplug infrastructure.
First of all, since notify handlers may be run in parallel with
acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device()
and some of them are installed for ACPI handles that have no struct
acpi_device objects attached (i.e. before those objects are created),
those notify handlers have to take acpi_scan_lock to prevent races
from taking place (e.g. a struct acpi_device is found to be present
for the given ACPI handle, but right after that it is removed by
acpi_bus_trim() running in parallel to the given notify handler).
Moreover, since some of them call acpi_bus_scan() and
acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock
should be acquired by the callers of these two funtions rather by
these functions themselves.
For these reasons, make all notify handlers that can handle device
addition and eject events take acpi_scan_lock and remove the
acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim().
Accordingly, update all of their users to make sure that they
are always called under acpi_scan_lock.
Furthermore, since eject operations are carried out asynchronously
with respect to the notify events that trigger them, with the help
of acpi_bus_hot_remove_device(), even if notify handlers take the
ACPI scan lock, it still is possible that, for example,
acpi_bus_trim() will run between acpi_bus_hot_remove_device() and
the notify handler that scheduled its execution and that
acpi_bus_trim() will remove the device node passed to
acpi_bus_hot_remove_device() for ejection. In that case, the struct
acpi_device object obtained by acpi_bus_hot_remove_device() will be
invalid and not-so-funny things will ensue. To protect agaist that,
make the users of acpi_bus_hot_remove_device() run get_device() on
ACPI device node objects that are about to be passed to it and make
acpi_bus_hot_remove_device() run put_device() on them and check if
their ACPI handles are not NULL (make acpi_device_unregister() clear
the device nodes' ACPI handles for that check to work).
Finally, observe that acpi_os_hotplug_execute() actually can fail,
in which case its caller ought to free memory allocated for the
context object to prevent leaks from happening. It also needs to
run put_device() on the device node that it ran get_device() on
previously in that case. Modify the code accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Commit 668192b678 "PCI: acpiphp: Move host bridge hotplug
to pci_root.c" has moved PCI host bridge hotplug logic from acpiphp
to pci_root, but there is still PCI host bridge hotplug related
dead code left in acpiphp. So remove those dead code.
Now companion ACPI devices are always created before corresponding
PCI devices. And the ACPI event handle_hotplug_event_bridge() will be
installed only if it has associated PCI device. So remove dead code to
handle bridge hot-adding in function handle_hotplug_event_bridge().
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
With commit 4f535093cf "PCI: Put pci_dev in device tree as
early as possible", companion ACPI devices should be created before
creating corresponding PCI devices, otherwise it will break the ACPI
PCI binding logic.
Without this patch, the /sys/bus/pci/devices/.../firmware_node symlink
is missing after hot-removing and hot-adding a device with acpiphp.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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>
* pci/yinghai-root-bus-hotplug:
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
PCI/ACPI: Print info if host bridge notify handler installation fails
PCI: acpiphp: Move host bridge hotplug to pci_root.c
PCI/ACPI: acpiphp: Rename alloc_acpiphp_hp_work() to alloc_acpi_hp_work()
PCI: Make device create/destroy logic symmetric
PCI: Fix reference count leak in pci_dev_present()
PCI: Set pci_dev dev_node early so IOAPIC irq_descs are allocated locally
PCI: Add root bus children dev's res to fail list
PCI: acpiphp: Add is_hotplug_bridge detection
Conflicts:
drivers/pci/pci.h
* pci/acpi-scan2:
ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() instead
ACPI: update ej_event interface to take acpi_device
ACPI / scan: Add second pass to acpi_bus_trim()
ACPI / scan: Change the implementation of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_device_unregister()
ACPI: Remove the ops field from struct acpi_device
ACPI: remove unused acpi_op_bind and acpi_op_unbind
ACPI / scan: Fix check of device_attach() return value.
* pci/yijing-ari:
PCI: shpchp: Iterate over all devices in slot, not functions 0-7
PCI: sgihp: Iterate over all devices in slot, not functions 0-7
PCI: cpcihp: Iterate over all devices in slot, not functions 0-7
PCI: pciehp: Iterate over all devices in slot, not functions 0-7
PCI: Consolidate "next-function" functions
PCI: Rename pci_enable_ari() to pci_configure_ari()
PCI: Enable ARI if dev and upstream bridge support it; disable otherwise
Since acpi_bus_trim() cannot fail, change its definition to a void
function, so that its callers don't check the return value in vain
and update the callers.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Could have root bus hot-added later and there may be slots that need
acpiphp.
The result returned by acpiphp_get_num_slots() is meaningless, because
the bridge the slots are under may be added after this function has been
called, so drop acpiphp_get_num_slots() and the code using it.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The acpiphp driver is confusing because it contains partial support for PCI
host bridge hotplug as well as support for hotplug of PCI devices.
This patch moves the host bridge hot-add support to pci_root.c and adds
hot-remove support in pci_root.c.
How to test it: if sci_emu patch is applied, find out root bus number to
ACPI root name mapping from dmesg or /sys. To remove root bus:
echo "\_SB.PCIB 3" > /sys/kernel/debug/acpi/sci_notify
To add back root bus:
echo "\_SB.PCIB 1" > /sys/kernel/debug/acpi/sci_notify
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Will need to use it for PCI root bridge hotplug support, so rename
*acpiphp* to *acpi* and move to osc.c. Also make kacpi_hotplug_wq static
after that.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
When system support hotplug bridge with children hotplug slots, we need
to make sure that parent bridge get preallocated resource so later when
device is plugged into children slot, those children devices will get
resource allocated.
We do not meet this problem, because for PCIe hotplug card, when acpiphp
is used, pci_scan_bridge will set that for us when detect hotplug bit in
slot cap.
Reported-and-tested-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix shpchp_unconfigure_device()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix disable_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7. It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.
ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.
[bhelgaas: changelog, check PCI_SLOT, fix cpci_unconfigure_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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>
The only difference between acpi_bus_scan() and acpi_bus_add() is the
invocation of acpi_update_all_gpes() in the latter which in fact is
unnecessary, because acpi_update_all_gpes() has already been called
by acpi_scan_init() and the way it is implemented guarantees the next
invocations of it to do nothing.
For this reason, drop acpi_bus_add() and make all its callers use
acpi_bus_scan() directly instead of it. Additionally, rearrange the
code in acpi_scan_init() slightly to improve the visibility of the
acpi_update_all_gpes() call in there.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
All callers of acpi_bus_trim() pass 1 (true) as the second argument
of it, so remove that argument entirely and change acpi_bus_trim()
to always behave as though it were 1.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
When we have an SHPC-capable bridge with a second SHPC-capable bridge
below it, pushing the upstream bridge's attention button causes a
deadlock.
The deadlock happens because we use the shpchp_wq workqueue to run
shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove
devices below the upstream bridge. When we remove the downstream bridge,
we call shpc_remove(), the shpchp driver's .remove() method. That calls
flush_workqueue(shpchp_wq), which deadlocks because the
shpchp_pushbutton_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every slot
and removing the single shared workqueue.
Here's the call path that leads to the deadlock:
shpchp_queue_pushbutton_work
queue_work(shpchp_wq) # shpchp_pushbutton_thread
...
shpchp_pushbutton_thread
shpchp_disable_slot
remove_board
shpchp_unconfigure_device
pci_stop_and_remove_bus_device
...
shpc_remove # shpchp driver .remove method
hpc_release_ctlr
cleanup_slots
flush_workqueue(shpchp_wq)
This change is based on code inspection, since we don't have hardware
with this topology.
Based-on-patch-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
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 shpchp as a result.
486b10b9f4 ("PCI: pciehp: Handle push button event asynchronously") made
the same change to pciehp. I split this out from a patch by Yijing Wang
<wangyijing@huawei.com> so we fix one thing at a time and to make the
shpchp history correspond more closely with the pciehp history.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
e24dcbef93 ("shpchp: update workqueue usage") was described as adding
non-ordered shpchp_wq, but it actually made it an *ordered* workqueue.
This patch changes shpchp_wq to be non-ordered, as described in the
e24dcbef93 commit log and as was done for pciehp by a827ea307b ("pciehp:
update workqueue usage").
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
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
