On ACPI-based platforms, the pci_slot driver creates PCI slot devices
according to information from ACPI tables by registering an ACPI PCI
subdriver. The ACPI PCI subdriver will only be called when creating/
destroying PCI root buses, and it won't be called when hot-plugging
P2P bridges. It may cause stale PCI slot devices after hot-removing
a P2P bridge if that bridge has associated PCI slots. And the acpiphp
driver has the same issue too.
This patch introduces two hook points into the PCI core, which will
be invoked when creating/destroying PCI buses for PCI host and P2P
bridges. They could be used to setup/destroy platform dependent stuff
in a unified way, both at boot time and for PCI hotplug operations.
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>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Myron Stowe <myron.stowe@redhat.com>
We always call device_register() and pci_create_legacy_files() for a
new bus before handing out the "struct pci_bus *". Therefore, there's
no possiblity of removing the bus with pci_remove_bus() before those
calls have been made, so we don't need to check "bus->is_added" before
calling pci_remove_legacy_files() and device_unregister().
[bhelgaas: changelog]
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>
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
...
Devices are added to pci_pme_list when drivers use pci_enable_wake()
or pci_wake_from_d3(), but they aren't removed from the list unless
the driver explicitly disables wakeup. Many drivers never disable
wakeup, so their devices remain on the list even after they are
removed, e.g., via hotplug. A subsequent PME poll will oops when
it tries to touch the device.
This patch disables PME# on a device before removing it, which removes
the device from pci_pme_list. This is safe even if the device never
had PME# enabled.
This oops can be triggered by unplugging a Thunderbolt ethernet adapter
on a Macbook Pro, as reported by Daniel below.
[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2svG21yiM1wkH4_2pen2n+cr2-Zv7TbH3Gj+8MwevZjDbw@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
According to device model documentation, the way to create/destroy PCI
devices should be symmetric. The rule is to either use
1) device_register()/device_unregister()
or
2) device_initialize()/device_add()/device_del()/put_device().
So change PCI core logic to follow the rule and get rid of the redundant
pci_dev_get()/pci_dev_put() pair.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
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>
It supports both PCI root bus and PCI bus under PCI bridge.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This restores the previous behavior of stopping all child devices before
removing any of them. The current SR-IOV design, where removing the PF
also drops references on all the VFs, depends on having the VFs continue
to exist after having been stopped.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
list_del() already sets next/prev to LIST_POISON1/LIST_POISON2, so we
don't need to do anything special here to prevent further list accesses.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Previously, when we removed a PCI device, we made two passes over the
hierarchy rooted at the device. In the first pass, we stopped all
the devices, and in the second, we removed them.
This patch combines the two passes into one so that we remove a device as
soon as it and all its children have been stopped.
Note that we previously stopped devices in reverse order and removed them
in forward order. Now we stop and remove them in reverse order.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
pci_stop_bus_devices() is only two lines of code and is only called by
pci_stop_bus_device(), so I think it's easier to read if we just fold it
into the caller. Similarly for __pci_remove_behind_bridge().
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
The PCMCIA CardBus driver was the only user of
pci_stop_and_remove_behind_bridge(), and it now uses
pci_stop_and_remove_bus_device() instead, so remove this interface.
This removes exported symbol pci_stop_and_remove_behind_bridge.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
The acpiphp hotplug driver was the only user of pci_stop_bus_device() and
__pci_remove_bus_device(), and it now uses pci_stop_and_remove_bus_device()
instead, so stop exposing these interfaces.
This removes these exported symbols:
__pci_remove_bus_device
pci_stop_bus_device
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Don't switch to pci_remove_bus_device yet, keep the __ prefix for now
(the behavior is still the same: remove without stopping first).
This allows other out of tree users or pending patches to get notified
from compiler warning.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The old pci_remove_behind_bridge actually do stop and remove.
Make the name reflect that to reduce confusion.
Suggested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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>
When hot removing a pci express module that has a pcie switch and supports
SRIOV, we got:
[ 5918.610127] pciehp 0000:80:02.2:pcie04: pcie_isr: intr_loc 1
[ 5918.615779] pciehp 0000:80:02.2:pcie04: Attention button interrupt received
[ 5918.622730] pciehp 0000:80:02.2:pcie04: Button pressed on Slot(3)
[ 5918.629002] pciehp 0000:80:02.2:pcie04: pciehp_get_power_status: SLOTCTRL a8 value read 1f9
[ 5918.637416] pciehp 0000:80:02.2:pcie04: PCI slot #3 - powering off due to button press.
[ 5918.647125] pciehp 0000:80:02.2:pcie04: pcie_isr: intr_loc 10
[ 5918.653039] pciehp 0000:80:02.2:pcie04: pciehp_green_led_blink: SLOTCTRL a8 write cmd 200
[ 5918.661229] pciehp 0000:80:02.2:pcie04: pciehp_set_attention_status: SLOTCTRL a8 write cmd c0
[ 5924.667627] pciehp 0000:80:02.2:pcie04: Disabling domain:bus:device=0000:b0:00
[ 5924.674909] pciehp 0000:80:02.2:pcie04: pciehp_get_power_status: SLOTCTRL a8 value read 2f9
[ 5924.683262] pciehp 0000:80:02.2:pcie04: pciehp_unconfigure_device: domain:bus:dev = 0000:b0:00
[ 5924.693976] libfcoe_device_notification: NETDEV_UNREGISTER eth6
[ 5924.764979] libfcoe_device_notification: NETDEV_UNREGISTER eth14
[ 5924.873539] libfcoe_device_notification: NETDEV_UNREGISTER eth15
[ 5924.995209] libfcoe_device_notification: NETDEV_UNREGISTER eth16
[ 5926.114407] sxge 0000:b2:00.0: PCI INT A disabled
[ 5926.119342] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 5926.127189] IP: [<ffffffff81353a3b>] pci_stop_bus_device+0x33/0x83
[ 5926.133377] PGD 0
[ 5926.135402] Oops: 0000 [#1] SMP
[ 5926.138659] CPU 2
[ 5926.140499] Modules linked in:
...
[ 5926.143754]
[ 5926.275823] Call Trace:
[ 5926.278267] [<ffffffff81353a38>] pci_stop_bus_device+0x30/0x83
[ 5926.284180] [<ffffffff81353af4>] pci_remove_bus_device+0x1a/0xba
[ 5926.290264] [<ffffffff81366311>] pciehp_unconfigure_device+0x110/0x17b
[ 5926.296866] [<ffffffff81365dd9>] ? pciehp_disable_slot+0x188/0x188
[ 5926.303123] [<ffffffff81365d6f>] pciehp_disable_slot+0x11e/0x188
[ 5926.309206] [<ffffffff81365e68>] pciehp_power_thread+0x8f/0xe0
...
+-[0000:80]-+-00.0-[81-8f]--
| +-01.0-[90-9f]--
| +-02.0-[a0-af]--
| +-02.2-[b0-bf]----00.0-[b1-b3]--+-02.0-[b2]--+-00.0 Device
| | | +-00.1 Device
| | | +-00.2 Device
| | | \-00.3 Device
| | \-03.0-[b3]--+-00.0 Device
| | +-00.1 Device
| | +-00.2 Device
| | \-00.3 Device
root complex: 80:02.2
pci express modules: have pcie switch and are listed as b0:00.0, b1:02.0 and b1:03.0.
end devices are b2:00.0 and b3.00.0.
VFs are: b2:00.1,... b2:00.3, and b3:00.1,...,b3:00.3
Root cause: when doing pci_stop_bus_device() with phys fn, it will stop
virt fn and remove the fn, so
list_for_each_safe(l, n, &bus->devices)
will have problem to refer freed n that is pointed to vf entry.
Solution is just replacing list_for_each_safe() with
list_for_each_prev_safe(). This will make sure we can get valid n pointer
to PF instead of the freed VF pointer (because newly added devices are
inserted to the bus->devices list tail).
During reviewing the patch, Bjorn said:
| The PCI hot-remove path calls pci_stop_bus_devices() via
| pci_remove_bus_device().
|
| pci_stop_bus_devices() traverses the bus->devices list (point A below),
| stopping each device in turn, which calls the driver remove() method. When
| the device is an SR-IOV PF, the driver calls pci_disable_sriov(), which
| also uses pci_remove_bus_device() to remove the VF devices from the
| bus->devices list (point B).
|
| pci_remove_bus_device
| pci_stop_bus_device
| pci_stop_bus_devices(subordinate)
| list_for_each(bus->devices) <-- A
| pci_stop_bus_device(PF)
| ...
| driver->remove
| pci_disable_sriov
| ...
| pci_remove_bus_device(VF)
| <remove from bus_list> <-- B
|
| At B, we're changing the same list we're iterating through at A, so when
| the driver remove() method returns, the pci_stop_bus_devices() iterator has
| a pointer to a list entry that has already been freed.
Discussion thread can be found : https://lkml.org/lkml/2011/10/15/141https://lkml.org/lkml/2012/1/23/360
-v5: According to Linus to make remove more robust, Change to
list_for_each_prev_safe instead. That is more reasonable, because
those devices are added to tail of the list before.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
During test busn_res allocation with cardbus, found pci card removal is not
working anymore, and it turns out it is broken by:
|commit 79cc9601c3
|Date: Tue Nov 22 21:06:53 2011 -0800
|
| PCI: Only call pci_stop_bus_device() one time for child devices at remove
The above changed the behavior of pci_remove_behind_bridge that
yenta_cardbus depended on. So restore the old behavoir of
pci_remove_behind_bridge (which requires stopping and removing of all
devices) by:
1. rename pci_remove_behind_bridge to __pci_remove_behind_bridge, and let
__pci_remove_bus_device() call it instead.
2. add pci_stop_behind_bridge that will stop devices behind a bridge
3. add back pci_remove_behind_bridge that will stop and remove devices
under bridge.
-v2: update commit description a little bit.
Tested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
During debugging pcie hotplug with SRIOV with pcie switch, I found
pci_stop_bus_device() is called several times for some child devices.
So change original pci_remove_bus_device() to __pci_remove_bus_device(),
and make it only do remove work, and add a new pci_remove_bus_device
that calls pci_stop_bus_device() one time, and then call
__pci_remove_bus_device().
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Requested by Greg KH to fix a race condition in the creating of PCI bus
cpuaffinity files.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We always call pci_stop_bus_device before calling pci_destroy_dev.
Since pci_stop_bus_device calls pci_stop_dev, there is no need
for pci_destroy_dev to repeat the call.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
